Amendment 84Mail Ballot Voter Identification
Read the full text of the measure: on this page or in the Blue Book (PDF, page 70)
In plain words
Amendment 84 would require people voting by mail to write the last four digits of an ID number with their ballot, along with signing the envelope. The number can come from a Social Security number, a Colorado driver's license, or a Colorado ID card that meets the federal Real ID standard. If the number is missing or does not match, the county must contact the voter. The ballot counts only if the voter fixes it within eight days after Election Day. source: Blue Book, p. 24
Before and after
| Question | Today | If Amendment 84 passes |
|---|---|---|
| What must a mail voter provide? | A signature on the envelope | A signature, plus the last 4 digits of a Social Security number, Colorado driver's license, or Colorado ID card |
| How is the ballot checked? | The signature is compared to the one on file | The signature check, plus the ID number is matched to voter records |
| If there is a problem, how long does the voter have to fix it? | 8 days after Election Day | 8 days after Election Day. The voter can also send a copy of an accepted ID, a U.S. passport, a U.S. military ID, or a tribal photo ID, in person or online. |
| ID rules for voting in person | No change | No change |
| Which elections? | Not applicable | Federal and statewide elections |
| Cost to state and local governments | No added cost today. The cost at right is what this measure would add | Up to $2.7 million in budget year 2026-27, then $1.2 million a year |
From the official analysis source: Blue Book, p. 24
Example
Illustration only: The Blue Book says counties would spend up to $2.5 million in budget year 2026-27. The state pays back about 45 percent of county costs, up to $1.1 million that year. That leaves counties paying roughly $1.4 million themselves. source: Blue Book, p. 24
Biggest change
- Mail voters would have to add the last four digits of an accepted ID number to their ballot, on top of their signature. A ballot with a missing or wrong number would not count unless the voter fixes it within eight days after Election Day. source: Blue Book, p. 24
Who it affects most: Mail voters, who cast 92 percent of all ballots in Colorado in 2024, and the county election offices that would check the numbers.
Cost to the state: Up to $2.7 million for the state and counties together in budget year 2026-27, then $1.2 million a year after that. The state's share has usually been paid from Department of State fees, not the General Fund (the state's main account for everyday spending). Business filing fees may go up to cover it.
Our plain-words summary at an 8th-grade reading level. Every line points to its source.
What your vote means
Mail voters must add the last four digits of an accepted ID number to their ballot, on top of their signature.
Mail ballots keep being checked by signature only.
Our plain-words summary.
The Blue Book's official wording of YES and NO (tap to open)
YES: A “yes” vote on Amendment 84 requires voters to provide identification information with their mail ballot, in addition to their signature.
NO: A “no” vote on Amendment 84 continues the current signature-only verification system for mail ballots.
Why people want it, and why others object
Why this is on the ballot
- Citizens put this on the ballot by gathering voter signatures (a citizen initiative). It would change the Colorado Constitution, the state's highest set of laws, which only a statewide vote can change. It needs 55 percent of the vote to pass. source: Blue Book, p. 24
- Every Colorado voter gets a mail ballot for federal and statewide elections, and in 2024, 92 percent of all ballots cast in Colorado were mail ballots. Today those ballots are checked only by comparing the voter's signature to the one on file. source: Blue Book, p. 24
Why supporters want it
- Additional voter verification for mail ballots strengthens election security while preserving convenient access to voting. Government-issued identification documents are more consistent and less subjective than the current signature verification process. Most voters already have an eligible identification card, or know their social security number. If a voter does not have one of the required forms of identification to complete their mail ballot, they can choose to vote in person using several identification options. Adding a convenient form of additional verification for mail ballots promotes public confidence that ineligible ballots will not be counted. source: Blue Book, p. 24
Why opponents object
- The measure adds an unnecessary burden to voting, without meaningfully improving election security. The measure could result in eligible voters’ ballots not being counted due to minor mistakes when submitting their mail ballot. Further, voters who have privacy concerns about providing sensitive information when submitting their ballot or who are unable to produce the required identification will be discouraged from using mail ballots, which is Colorado's most commonly used and convenient method of voting. The current signature verification process is effective, secure, and convenient for voters and it successfully identifies the rare cases when ineligible individuals attempt to submit a mail ballot. source: Blue Book, p. 24
Who backs each side
Totals are from the state campaign finance filings (TRACER), through October 14, 2026, pulled October 25, 2026. Spending grows until Election Day.
- For: Colorado Voter Trust Initiative reported $6.6 million, including $2.4 million from American Prosperity Caucus (Texas), $2.2 million from Coalition for American Prosperity & Growth (Colorado Springs), $1 million from A Public Voice (Virginia) and $1 million from American Jobs and Growth Fund (Virginia). These groups do not disclose their own donors.
- Against: Defend Our Ballots Issue Committee reported $236,000 through Oct 14, all from Colorado donors (a Denver nonprofit gave $161,000, plus two individuals).
Sources: Rocky Mountain Voice, Oct 6, 2026 · Colorado Politics, Sept 25, 2026 · Colorado Secretary of State: committees for and against 2026 measures · TRACER campaign finance search · Governing, Sept 2026 · Colorado Politics, Oct 2, 2026
Supporter and opponent arguments are the official ones printed in the Blue Book, written by the Legislative Council's nonpartisan staff after hearing from both sides. Who is registered for and against (Secretary of State) . We don't endorse either side.
Follow the money
Amendment 84 has the clearest money trail of any Colorado measure this year. The table below comes straight from the state's campaign finance filings (TRACER), pulled October 25, 2026. It covers reports through October 14, 2026 (filed October 19).
| Who gave | Where based (per filing) | Amount | Date | Source |
|---|---|---|---|---|
| Coalition for American Prosperity & Growth, Inc. | Colorado Springs, CO | $725,000 | 06/01/2026 | TRACER, committee ID 20265052101, pulled Oct 25, 2026 |
| Coalition for American Prosperity & Growth, Inc. | Colorado Springs, CO | $725,000 | 06/18/2026 | |
| Coalition for American Prosperity & Growth, Inc. | Colorado Springs, CO | $750,000 | 07/01/2026 | |
| A Public Voice | McLean, VA | $1,000,000 | 09/11/2026 | |
| American Jobs and Growth Fund | Alexandria, VA | $1,000,000 | 09/11/2026 | |
| American Prosperity Caucus | Euless, TX | $2,400,000 | 10/01/2026 |
Receiving committee: Colorado Voter Trust Initiative (supports Amendment 84, mail ballot voter identification). Through October 14, 2026 it reported $6,600,000 in contributions and $5,750,055 in spending, with $849,945 left.
Our math: the six gifts add up to $6,600,000, which matches the committee's reported total. By the addresses in the filing, $4,400,000 is from outside Colorado (Virginia $2,000,000 and Texas $2,400,000) and $2,200,000 is from a Colorado Springs group. Filings do not say who funds these groups.
How sure are we? Each claim, checked October 25, 2026
| Claim | Status | What we know | Sources |
|---|---|---|---|
| The yes committee has raised $6.6 million through October 14. | Official source | Six contributions in the committee's filings add up to $6,600,000, matching its financial summary. | TRACER, 20265052101 |
| $4.4 million of it is from outside Colorado. | Official source | Donor addresses in the filing: McLean VA, Alexandria VA, Euless TX. The rest ($2.2 million) lists a Colorado Springs address. | TRACER, 20265052101 |
| The $2.2 million donor is named Coalition for American Prosperity & Growth, Inc. | Official source | The filing uses this name. Governing and Colorado Politics each gave a different name, and Governing placed the group in Ohio. The filing lists Colorado Springs. | TRACER, 20265052101 |
| American Jobs and Growth Fund is funded by Club for Growth. | One source only | Stated by one outlet. We have not found a second source or a filing. | Colorado Politics, Oct 14 |
| The opposing committee has raised $236,000 through October 14. | Official source | Defend Our Ballots Issue Committee: five contributions add up to $236,000, all from Colorado addresses. Defend Our Ballots 501(c)(4), Denver, gave $161,000 in three gifts; John Powers of Boulder gave $50,000; Merle Chambers of Denver gave $25,000. It reported $75,000 in spending. Earlier news reports had put it at $0. | TRACER, 20265052411 |
| The measure would cost the state and counties up to $2.7 million in 2026-27, then about $1.2 million a year. | Official source | From the nonpartisan Legislative Council fiscal estimate in the Blue Book. | 2026 Blue Book (PDF) |
Status key: Official source a government document. One source only or News reports only treat as unconfirmed.
Correction history
- 2026-10-25 Added the opposing committee from its filings. The page had said no money was reported against Amendment 84 ($0 through Oct 4). TRACER shows $236,000 raised and $75,000 spent through Oct 14.
- 2026-10-25 Corrected after opening the filings in TRACER. The page had said the yes committee raised about $4.2 million, all from groups outside Colorado, with a $2.2 million donor in Ohio. The filing shows $6.6 million in six contributions: $4.4 million from Virginia and Texas groups and $2.2 million from a Colorado Springs group. The donor's name now follows the filing. Donor amounts, dates and cities now come from the filing, not from news reports.
- 2026-10-25 Earlier the same day: money figures moved from 'as of Sept 21' to 'through Sept 30', and a note was added that two outlets gave different names for the $2.2 million donor.
Check it yourself: search TRACER for the committee 'Colorado Voter Trust Initiative' and read its contributions list. If you find a difference from this page, tell us and it goes in the log above. Open TRACER
At a glance
Our plain-words summary of the official Blue Book analysis. Every line points to its source.
Who it affects
- Voters who vote by mail in federal and statewide elections. They would have to write the last four digits of a Social Security number, a Real ID-compliant Colorado driver's license, or a Real ID-compliant Colorado ID card on their ballot. (Blue Book, p. 24 )
- Voters whose ID number is missing or does not match. Their ballot is not counted unless they confirm their identity within eight days after election day. (Blue Book, p. 24 )
- Voters with qualifying physical disabilities and elderly voters entitled by federal law to vote by mail. They may use a broader range of ID. (Blue Book, p. 24 )
- County election offices and election judges, who must check ID numbers, contact voters about problems, and update envelopes and systems. (Blue Book, p. 24 )
- The Colorado Department of State, which must run voter outreach and pay back part of county costs. (Blue Book, p. 24 )
- Businesses that pay state filing fees. The Blue Book says those fees may need to be raised to cover the costs. (Blue Book, p. 24 )
How many: Every Colorado voter gets a mail ballot for federal and statewide elections, and in 2024, 92 percent of all ballots cast in Colorado were mail ballots. The Blue Book does not say how many voters lack an accepted ID number or how many ballots might go uncounted.
Money: economic and budget impact
- Total: state and local spending rises by up to $2.7 million in budget year 2026-27 and $1.2 million a year after that, for voter outreach, printing and election staff. (Blue Book, p. 24 )
- Counties: spending rises by up to $2.5 million in 2026-27 and up to $1.2 million in future years. The state pays back about 45 percent of county costs. (Blue Book, p. 24 )
- State: the Department of State pays up to $1.1 million in 2026-27 and up to $500,000 in future years to pay back counties. It also spends $100,000 in 2026-27 and $200,000 in 2027-28 on an outreach campaign, plus about $20,000 for each presidential primary, statewide primary and general election. (Blue Book, p. 24 )
- Who pays: historically these costs come from Department of State fees and other revenue, not the state General Fund. Business filing fees may need to go up. The department would set which fees, when and how much. (Blue Book, p. 24 )
For federal and statewide elections, mail voters must add the last four digits of an accepted ID number, on top of signing the envelope. If the number is missing or does not match, the county must contact the voter, who has eight days after election day to fix it, in person or digitally. ID rules for in-person voting do not change. Because it is a constitutional amendment, changing it later would take another statewide vote.
Mail ballots stay under signature-only checks. Counties compare the envelope signature to the voter's signature on file. If two election judges from different parties agree it likely does not match, the county contacts the voter, who has eight days after election day to confirm their identity.
Not yet known
- How many registered voters do not have an accepted ID number (Social Security number or Real ID-compliant Colorado license or ID).
- How many mail ballots might be set aside or not counted because of missing or mismatched numbers.
- Which business filing fees would rise, and by how much.
- When the requirement first applies. The Blue Book does not give a start date.
Can it actually be enforced?
Short answer: The state can largely carry it out, since states run their own election procedures. But federal voting law sets some limits, and lawsuits over rejected ballots are possible.
- It is a constitutional amendment, so the legislature could not repeal it. County election offices would carry it out, with state funding for part of the cost. The Blue Book says business filing fees may rise to pay the state's share. (Blue Book, p. 24 )
- The amendment already builds in federal protections. Elderly and disabled voters entitled under federal law to vote by mail could use a wider range of ID. Voters with a missing or mismatched number must be contacted and get eight days after the election to fix it. (Blue Book, p. 24 )
- A federal law bars denying anyone the right to vote over an error or omission on a voting record or paper, if the error is not material to whether the person is qualified to vote. 'Vote' includes having the ballot counted. Courts in other states have heard claims under this law about mail ballot envelope rules. Whether it would apply to an ID number mismatch is a question a court would decide. (law.cornell.edu )
- Congress has the final say over rules for federal elections under the U.S. Constitution's Elections Clause. The Supreme Court has said Congress can 'make or alter' state election rules. Congress has not passed a law that blocks this kind of ID check, as far as we have confirmed. (supreme.justia.com )
- The measure applies to federal and statewide elections. It does not change ID rules for in-person voting. (Blue Book, p. 24 )
Not yet known
- Whether any lawsuit is planned, and how courts would treat ballots rejected for a wrong digit. We did not find a ruling on this exact kind of rule.
This is our reading of the cited law, not legal advice. Court outcomes are uncertain.
Official ballot wording
Official ballot wording, word for word (tap to open)
The ballot title, word for word from the 2026 Blue Book.
Shall there be an amendment to the Colorado Constitution requiring a voter to sign and include the last four digits of their social security number or their Colorado driver’s license or identification card number on the outside of their mail ballot for any federal or state election, and, in connection therewith, allowing the voter to correct missing or incorrect information, including with alternative forms of identification; and prohibiting a county clerk and recorder from counting the mail ballot unless the problem is fixed?
The official analysis
The full Blue Book analysis, word for word (tap to open)
Everything in this section is quoted from the nonpartisan Legislative Council's 2026 State Ballot Information Booklet (the Blue Book). Charts are described in words. Read the full Blue Book (PDF)
Amendment 84 proposes amending the Colorado Constitution to:
- require voters to provide identification information, in addition to their signature, for their mail ballots to be counted.
Summary and Analysis of Amendment 84
What does this measure do?
For federal and statewide elections, the measure requires voters to include the last four digits of a government-issued identification number when submitting their mail ballot. Acceptable forms of identification are a social security number, a Colorado driver’s license number, or a Colorado identification card number. Any form of Colorado identification provided must be compliant with the federal Real ID law. This new verification process created by the measure is in addition to the current signature verification process for mail ballots.
If a voter’s identification information is missing or cannot be matched to the state voter registration database, the county election office must contact the voter to tell them how to correct the discrepancy. Consistent with the existing signature verification process, the ballot will not be counted unless the voter takes steps within eight days of election day to confirm their identify. Specifically, a voter may submit a copy of one of the forms of identification allowed under the measure. Alternately, a voter may provide a copy of a U.S. passport, a U.S. military identification card, or a tribal photo identification card. During this process, identification may be provided in-person or digitally. Voters with qualifying physical disabilities or elderly voters who are entitled under federal law to vote by mail may submit a broader range of acceptable forms of identification.
What is the role of mail ballots in Colorado elections?
Every Colorado voter receives a mail ballot for federal and statewide elections. Coloradans can vote by returning their mail ballot at a drop box or through the mail, or they may vote in person at any voter service and polling center in their county. In 2024, 92 percent of all ballots cast in Colorado were mail ballots, most of which were returned to a drop box.
How are mail ballots verified under current law?
Colorado currently uses signature verification to determine that mail ballots come from eligible voters. When a voter returns a mail ballot, they must sign the envelope. Once the ballot is received by the county election office, the signature on the envelope is then compared to the voter’s signature on file from election and driver’s license records. If a signature discrepancy is found, the signature is then reviewed by two election judges of different political parties. If they both agree that the signature likely does not belong to the voter, the county election office must contact the voter to have them confirm their identity and that they submitted the ballot. If the voter does not confirm their identity within eight days after election day, the ballot is not counted.
Does the measure affect the allowable forms of identification for in‑person voting?
No. The measure does not change the forms of identification that may be presented when voting in person at a voter service and polling center. The allowable forms of identification for in-person voting are broader than those required for mail ballots under this measure, including documents that show a person’s name and address.
Argument For Amendment 84
1) Additional voter verification for mail ballots strengthens election security while preserving convenient access to voting. Government-issued identification documents are more consistent and less subjective than the current signature verification process. Most voters already have an eligible identification card, or know their social security number. If a voter does not have one of the required forms of identification to complete their mail ballot, they can choose to vote in person using several identification options. Adding a convenient form of additional verification for mail ballots promotes public confidence that ineligible ballots will not be counted.
Argument Against Amendment 84
1) The measure adds an unnecessary burden to voting, without meaningfully improving election security. The measure could result in eligible voters’ ballots not being counted due to minor mistakes when submitting their mail ballot. Further, voters who have privacy concerns about providing sensitive information when submitting their ballot or who are unable to produce the required identification will be discouraged from using mail ballots, which is Colorado's most commonly used and convenient method of voting. The current signature verification process is effective, secure, and convenient for voters and it successfully identifies the rare cases when ineligible individuals attempt to submit a mail ballot.
Information about the organizations supporting and opposing this measure is available on the Colorado Secretary of State's website:
www.coloradosos.gov/pubs/elections/Initiatives/ballot/contacts/2026.html
Fiscal Impact of Amendment 84
The measure will increase state and local spending by up to $2.7 million in the initial budget year 2026-27, and $1.2 million annually in future years for voter outreach, printing, and election staff to verify voter information. These costs will be divided between state and local governments as discussed below.
Local Government Spending
The new verification process under the measure will increase county spending by up to $2.5 million in the 2026-27 budget year and up to $1.2 million in future years. About 45 percent of these county costs will be reimbursed by the state government. These costs are driven from several new requirements under the measure. First, election judges must review identification numbers provided by voters, which will increase staffing hours and overtime during elections. Second, county election offices must notify voters of any discrepancies involving their identification information, which will require sending a postcard or digital notification to voters and segregating ballots until valid identification is provided. Lastly, county election offices will also be required to update ballot materials and envelopes, modify various elections systems, and conduct voter outreach.
State Spending
The Department of State will have increased costs to inform voters of the changes to mail voting across the state and to reimburse counties. Specifically, the department will need to conduct an outreach and communication campaign at a cost of $100,000 in state budget year 2026-27 and $200,000 in state budget year 2027-28. The department will also have ongoing workload and costs for outreach and printed materials estimated at $20,000 for each presidential primary, statewide primary, and general election. As discussed above, the state will also have costs to reimburse counties for a portion of their costs under the measure. This reimbursement is estimated to be up to $1.1 million in during the 2026-27 budget year, and up to $500,000 for in future years. Historically, these costs have been paid using fees and other revenue collected by the department, rather than from the state General Fund.
State Revenue
To cover the costs in the Department of State discussed above, business filing fees may need to be raised to cover all or some of the costs of this measure. The fees affected, the timing of any increase, and the actual amount of fee charges will be set administratively by the department based on its available fund balance and total program costs.
Latest news
Recent reporting from a range of outlets, newest first. We link to it; we don't endorse it.
- 2026-10-03 The Colorado Sun: Amendment 84 explained: ID numbers on Colorado ballots
- 2026-10-02 Colorado Politics: Amendment 84: identification for voting by mail
- 2026-09-25 CPR News: Amendment 84: Mail Ballot Voter Identification
- 2026-09-23 Colorado Newsline: ID number would have to appear on Colorado mail ballots if amendment passes
- 2026-08-27 Complete Colorado: Voter ID for mail ballots makes Colorado's November election
- 2026-08-26 The Colorado Sun: Colorado voters will be asked to force people to add ID info to mail ballots
Coverage of all the statewide measures
- 2026-10-06 Rocky Mountain Voice: What's on your 2026 Colorado ballot: all 14 statewide measures
- 2026-09-25 Colorado Politics: Major donors fuel Colorado ballot measure fights across the state
- 2026-09-25 CPR News: 2026 Colorado state ballot measures voter guide
Full text of the measure
Word for word from the Blue Book, pages 70 to 71 (PDF ). Where the measure changes existing statutes, new wording is in CAPITAL LETTERS, as in the printed booklet.
Show the full text
Be it enacted by the People of the State of Colorado:
SECTION 1. In the constitution of the state of Colorado, add Section 13 to article VII as follows:
Section 13. Voter Authentication
(1) For any federal or statewide election, a voter is required to affix their signature and include either the last four digits of their social security number or Colorado real identification number or Colorado real identification driver’s license number, as codified in 49 U.S.C. sec. 30301 note or its successor section and sections 42-2-101, 42-2-301, and 42-2-402 or their successor sections, on the self-affirmation of a returned
mail ballot. A voter may alternatively include the last four digits of another form of Colorado identification that meets the requirements of the Federal Real ID Act of 2005 or successor legislation. if the voter fails to fill out all or part of the required affirmation, or if an election judge is unable to confirm that the information provided matches the voter’s information contained in the statewide voter registration database, the county clerk and recorder or other designated election official must send notice to the voter informing them of the process to correct the discrepancy. The county clerk and recorder shall not count the ballot until the discrepancy is corrected.
(2) A discrepancy may be corrected by providing a copy of the voter’s identification in subsection (1) of this section, US passport, US Military Identification card, or tribal photo identification, in person or digitally, to the county clerk and recorder or other designated election official.
(3) Notwithstanding subsection (2) of this section, a voter who is provided the right to vote otherwise than in person under section (b)(2)(B)(ii) of the federal “Voting Accessibility for the Elderly and Handicapped Act”, 52 U.S.C. sec. 20102 et seq., may provide any form of identification deemed acceptable under section 1-1-104 (19.5) or its successor to correct a discrepancy.
Read more
- 2026 Blue Book (PDF) , including the full legal text of the measure
- Colorado Secretary of State: who is registered for and against
- TRACER: Colorado campaign finance filings
What people are saying
Official campaign accounts on each side, and public posts. Links only: nothing here loads from social media sites. We link to posts; we don't endorse them.
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