How to modify child support or maintenance in Colorado

Sources last checked: 3 November 2026. Information only, not legal advice. The Cusp is not a law firm.

Colorado divorce kit How child support is calculated Alimony in Colorado Legal aid in Colorado After your divorce: changing a support or custody order

The short version

In Colorado, child support and maintenance (the state’s word for spousal support) are both changed by filing a motion in your existing divorce case, under section 14-10-122 of the Colorado Revised Statutes. For child support you must show “changed circumstances that are substantial and continuing”. For maintenance the changed circumstances must be so substantial and continuing “as to make the terms unfair”. A change can reach back only to the date you file the motion, and not before. The Colorado Judicial Branch publishes statewide forms: JDF 1403, Motion to Modify Child Support, and JDF 1401, Motion/Stipulation to Modify or Terminate Maintenance, with step-by-step instructions for each.

What the motion can ask for

Child support: a change in circumstances that is “substantial and continuing”, or an order that has no provision on medical support. The Judicial Branch page says a substantial change is one that moves the guideline amount up or down by at least 10%. The instructions list a permanent income change and a child becoming emancipated (when support is ordered for two or more children) as examples, and say “Added expenses (such as a new car, house, etc.) do not qualify”.
Maintenance: a change in circumstances “so substantial and continuing as to make the terms unfair”, either to change the amount or to end maintenance. The Judicial Branch page describes it as a change so that the current arrangement “no longer makes sense and is unfair”.
If you and the other party agree: both the child support and maintenance packets offer a stipulation (a written agreement signed by both parties) instead of a contested motion. For child support the stipulation is JDF 1404.

What else you file

Child support motion (JDF 1403): the instructions (JDF 1403 i, revised 13 July 2026) also list a Certificate of Compliance with mandatory disclosure (JDF 1104), a Sworn Financial Statement (JDF 1111) and a Child Support Worksheet (JDF 1820). The certificate and the financial statement are due within 42 days of the date the motion was served. Some counties also want a proposed Support Order (JDF 1117) or Order re: Modification of Child Support (JDF 1405), with only the caption filled in.
Maintenance motion (JDF 1401): the instructions (JDF 1399) list the motion and an Order to Modify or Terminate Maintenance (JDF 1402), with only the caption completed.
Worksheets: the Judicial Branch points to its Family Law Software for the child support worksheet. To calculate maintenance only, it says to use the child support calculator and delete all the children.
Proof of service: both motions have a Certificate of Service. The maintenance instructions say the court must know all parties are aware of the motion before it acts.

What the statutes say

Wording below is a plain-language summary of the Colorado Revised Statutes as we read them on 3 November 2026, with short quotations. We read the 2024 edition published by the Office of Legislative Legal Services, then checked the later session acts described under “What we could not confirm”.

Timing, section 14-10-122(1)(a): maintenance may be modified “only as to installments accruing subsequent to the motion for modification”, and child support only for installments accruing after the filing of the motion. For maintenance the showing is changed circumstances “so substantial and continuing as to make the terms unfair”. For child support it is changed circumstances “that are substantial and continuing”, or an order with no medical support provision.
The 10% rule, section 14-10-122(1)(b): applying the guidelines to the circumstances at the time of the motion, a result with “less than a ten percent change in the amount of support due per month” is deemed not to be a substantial and continuing change.
Past-due amounts, section 14-10-122(1)(c): a support payment becomes a final money judgment “when it is due and not paid”, and is not retroactively modified except as the statute allows.
Effective date, section 14-10-122(1)(d): a modification should take effect on the date the motion was filed, unless the court finds that doing so would cause “undue hardship or substantial injustice”. The statute says the order may not be “retroactively modified prior to the date of filing”, except where the parents agreed to a change in physical custody. The court may change installments due between the filing and the order even if the circumstances no longer exist when the order is entered.
Change of physical care, section 14-10-122(5): when a court-ordered, voluntary or agreed change of physical care occurs, child support can be modified or ended as of the date care changed, but the court may not reach back more than five years before the motion unless that would be substantially inequitable, unjust or inappropriate.
When maintenance ends, section 14-10-122(2)(a): unless agreed in writing or stated in the decree, the duty to pay future maintenance ends on the earliest of the death of either party, the end of the maintenance term “unless a motion for modification is filed prior to the expiration of the term”, the recipient’s remarriage or civil union, or a court order ending it.
Agreements, sections 14-10-114(5)(a) and 14-10-112(6): an award of maintenance may be modified or ended under section 14-10-122 “Except upon written agreement of the parties”. Section 14-10-112(6) says a decree may “expressly preclude or limit modification” of its terms if the separation agreement so provides, except for terms about the children.
Guideline amount in a modification, section 14-10-114(5): the court may consider the guideline amount and term of maintenance and the statutory factors only in a modification or ending of a maintenance award entered on or after 1 January 2014. For awards entered before that date, the enactment of the guideline section is not a substantial and continuing change.
Annual exchange, section 14-10-115(14): when a child support order is entered or modified, the parties are to exchange financial information once a year or less often to update the order without a hearing. Subsection (14)(c) says an agreement to modify child support is “not effective until approved by the court”.
Ending child support, section 14-10-122(3): unless agreed or stated in the decree, child support ends on the child’s emancipation but not on the death of a parent who owes it.
2025 and 2026 acts: House Bill 25-1159 (child support commission recommendations) amended section 14-10-122 only in subsection (6)(d), a paternity provision. It also changed section 14-10-115, including the parenting-time and shared-care provisions, effective 1 March 2026, and the potential-income rule for maintenance in section 14-10-114(8)(c)(IV). House Bill 26-1217 corrects cross references in the child support guidelines.

Notice, service and hearing

Where to file: the Judicial Branch says to file online through Colorado Courts E-Filing, or with the same court that gave you the original order, and to pay the filing fee.
Copies: the child support instructions say any document filed “must also be mailed to every party in the case”, including the county child support office if it is involved. Service for a later filing can be by e-filing, regular mail or hand delivery, as the Certificate of Service shows. The Judicial Branch’s service page lists personal service options for a first filing, and says a waiver of service may be possible if the other person agrees.
Response: the child support motion says a response (JDF 1315) is due within 21 days of the service date. The maintenance motion form says the same.
Court review: both sets of instructions say that within 49 days of filing, the court reviews the matter and either decides it on the papers or schedules a hearing. The child support instructions add that the court may require mediation or a status conference before a hearing.
After an order: both sets of instructions say that if the amount changes, you must also change the income assignment (wage withholding). For maintenance, the obligor takes the order to the employer.

Before you file

The Judicial Branch pages say their standard instructions are for information only and are not legal advice about your case. See legal aid in Colorado for free or low-cost help, or the Colorado divorce kit for the wider process.
Fee we can state: the Judicial Branch list of fees shows $105 for a motion to modify a decree or final order more than 60 days after the order, and $146 for a response. The page says its figures reflect January 2025 and are subject to change. The maintenance instructions (rev. 9-17) also name $105 and a way to ask the court to file without payment. Service fees vary and are not paid to the court.
Check the version: the child support instructions are revised July 2026, but the JDF 1403 form file we read is marked September 2020, and the maintenance instructions and form are marked 2017 and 2018. Confirm you have the current versions.
Child support amounts follow the state guidelines. See how child support is calculated in Colorado and alimony in Colorado.

What we could not confirm

The current official text. The statute text we read is the 2024 printout from the legislature’s drafting office. The legislature’s link to its current searchable statutes goes to a LexisNexis site that would not load without a browser session, which we did not work around. We checked the bill pages for 2025 and 2026 acts we knew of, but cannot rule out another act that touched sections 14-10-114, 14-10-115 or 14-10-122.
House Bill 25-1159. We read the signed act, which is a scanned PDF, with text recognition, so we describe only its section numbers and effective dates.
House Bill 26-1217. We read only the legislature’s bill summary. The bill file would not open, so we have not read its text.
The rest of the guidelines. We did not read the child support schedule, the parenting-time adjustment as amended, or how the 10% test is computed.
Court rules. The instructions cite Colorado Rule of Civil Procedure 16.2(c) for the 49-day review. We did not read the rule.
Older forms. The maintenance instructions (JDF 1399, R9-17), the maintenance form (JDF 1401, R2-18) and the JDF 1403 form (R Sept. 3, 2020) are older revisions than the page links suggest. We have not compared the older and newer versions line by line.
Court fees. The $105 and $146 figures come from a Judicial Branch page that says it reflects January 2025. We did not check the statute that sets them.
Local practice. Counties differ on proposed orders and on mediation. The instructions say to check with the local self-help center.

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