First, get your current guideline amount from your state's calculator using today's income and custody numbers. Then compare it to your existing order below.
Modification threshold by state
| State | Threshold | Statute |
|---|---|---|
| Alabama | 10% change | Ala. R. Jud. Admin. 32(A)(2) |
| Alaska | 15% change | Alaska R. Civ. P. 90.3(h) |
| Arizona | 15% change or $50/mo change | A.R.S. §§ 25-327, 25-503 |
| Arkansas | 20% change | Ark. Code Ann. § 9-14-107 |
| California | 20% change or $50/mo change | 22 Cal. Code Regs. § 115535 (local child support agency review); general modification authority under Fam. Code § 3651 |
| Colorado | 10% change | C.R.S. § 14-10-122 |
| Connecticut | 15% change | Conn. Gen. Stat. § 46b-86 |
| Delaware | 10% change, 2.5+ yr since last order | Delaware Family Court Child Support Formula / Melson Formula rules (13 Del. C. Ch. 5, implemented via Family Court Rule and DCSS practice) |
| District of Columbia | 15% change | D.C. Code § 16-916.01(r)(4)(A) |
| Florida | 15% change or $50/mo change | Fla. Stat. § 61.30(1)(b) |
| Georgia | No fixed statutory percentage — general "substantial change in circumstances" standard | O.C.G.A. § 19-6-15 |
| Hawaii | 10% change, 3+ yr since last order | Haw. Rev. Stat. § 576D-7 |
| Idaho | 15% change or $50/mo change | IDAPA 16.03.03.300 (Idaho Dept. of Health & Welfare, Rules Governing Child Support Services) |
| Illinois | 20% change or $10/mo change, 3+ yr since last order | 750 ILCS 5/510 |
| Indiana | 20% change, 1+ yr since last order | Ind. Code § 31-16-8-1 |
| Iowa | 10% change | Iowa Code § 598.21C |
| Kansas | 10% change, 3+ yr since last order | Kansas Child Support Guidelines (Kansas Supreme Court administrative order), implementing K.S.A. § 23-3005 |
| Kentucky | 10% change | KRS 403.213 |
| Louisiana | 25% change | La. R.S. 9:311 |
| Maine | 15% change, 3+ yr since last order | 19-A M.R.S. § 2009 |
| Maryland | No fixed statutory percentage — general "substantial change in circumstances" standard | Md. Code, Family Law § 12-104 |
| Massachusetts | No fixed statutory percentage — general "substantial change in circumstances" standard | M.G.L. c. 208, § 28 / Massachusetts Child Support Guidelines, Section III (Modification) |
| Michigan | 10% change or $50/mo change | MCL § 552.517 (triennial Friend-of-the-Court review); numeric trigger set by the Michigan Child Support Formula Manual (State Court Administrative Office) |
| Minnesota | 20% change or $75/mo change | Minn. Stat. § 518A.39 |
| Mississippi | No fixed statutory percentage — general "substantial change in circumstances" standard | Miss. Code Ann. § 43-19-34; § 43-19-101 |
| Missouri | 20% change | Mo. Rev. Stat. § 452.370 |
| Montana | 30% change, 3+ yr since last order | Mont. Code Ann. § 40-4-208 (general modification standard); Admin. R. Mont. 37.62.2103 (CSSD review availability / 30% threshold) |
| Nebraska | 10% change or $25/mo change | Neb. Ct. R. § 4-217 (Nebraska Child Support Guidelines) |
| Nevada | 20% change, 3+ yr since last order | NRS 125B.145 |
| New Hampshire | 20% change, 3+ yr since last order | RSA 458-C:7 |
| New Jersey | No fixed statutory percentage — general "substantial change in circumstances" standard | N.J. Court Rule 5:6B |
| New Mexico | 20% change, 1+ yr since last order | NMSA 1978 § 40-4-11.1 |
| New York | 15% change, 3+ yr since last order | Family Court Act § 451; Domestic Relations Law § 236(B)(9)(b) |
| North Carolina | 15% change, 3+ yr since last order | N.C. Gen. Stat. § 50-13.7 |
| North Dakota | 15% change or $50/mo change, 1+ yr since last order | N.D.C.C. § 14-09-08.4 |
| Ohio | 10% change | Ohio Rev. Code § 3119.79 |
| Oklahoma | 20% change | 43 O.S. § 118I |
| Oregon | 15% change or $50/mo change | OAR 137-055-3430 (implementing ORS 25.287) |
| Pennsylvania | 20% change, 3+ yr since last order | 231 Pa. Code Rule 1910.19 |
| Rhode Island | 10% change, 3+ yr since last order | R.I. Gen. Laws § 15-5-16.2 (general modification standard); § 15-5-16.7 (3-year review) |
| South Carolina | 20% change | S.C. Code Ann. § 63-17-470; S.C. Code Regs. 114-4710 |
| South Dakota | 20% change, 3+ yr since last order | SDCL § 25-7A-22 (see also SDCL § 25-7-6.9) |
| Tennessee | 15% change | Tenn. Comp. R. & Regs. 1240-02-04-.05 |
| Texas | 20% change or $100/mo change, 3+ yr since last order | Tex. Fam. Code § 156.401(a)(2) |
| Utah | 15% change, 3+ yr since last order | Utah Code § 78B-12-210(8)-(9) |
| Vermont | 10% change, 3+ yr since last order | 15 V.S.A. § 660 |
| Virginia | No fixed statutory percentage — general "substantial change in circumstances" standard | Va. Code § 20-108 |
| Washington | 15% change, 2+ yr since last order | RCW § 26.09.170 |
| West Virginia | 15% change | W. Va. Code § 48-11-105 |
| Wisconsin | 15% change or $50/mo change | Wis. Stat. § 767.59 |
| Wyoming | 20% change, 3+ yr since last order | Wyo. Stat. § 20-2-311 |
Only states with a verified, cited primary source are listed. More states will be added as they're researched and verified — see our methodology.
FAQ
How much does income need to change to modify child support?
It depends entirely on your state. Many states set a specific percentage (commonly 10-20%) or dollar-amount change as a threshold; others use a general "substantial change in circumstances" standard with no fixed number. See the table above for your state's rule.
Where do I get my "new" guideline amount to compare?
Run your current income and custody numbers through your state's own child support calculator on this site, then enter that result here alongside your existing order amount.