Child support on $45,000 a year in Montana (2 children)
Montana guidelines effective February 1, 2026. Montana overview
If Parent A earns $45,000 a year, Parent B earns $40,000 and the children live mostly with Parent B (52 overnights a year with Parent A), Montana's guideline amount is $578 a month (Parent A pays Parent B).
Across the table below it ranges from $554 paid by Parent B (Parent B earns $100,000, equal time) to $886 (Parent B has no income, Parent A has no overnights).
This is the guideline amount, not a court order.
Change the numbers
Guideline child support
Montana · 2 children · Parent A $45000 per year · Parent B $40000 per year · children live mostly with Parent B
$578 a month
Parent A pays Parent B
- Parent A: 43% of combined income
- Parent B: 57%
How it adds up
- Combined income
- $37,787 a year
- Basic obligation
- $10,374 a year
- Parent A's share of income
- 43%
- Guideline amount
- $6,936 a year
See the worksheet for this example
- Net income was estimated with Montana's standard assumptions (single filer, 2026 tax year). Your actual taxes may differ.
Montana uses the Melson formula model under MCA 40-4-204, 40-5-209, 40-6-116; Admin. R. Mont. 37.62.101–37.62.148. Official worksheet: Montana Child Support Guidelines Worksheets A–E. Child support agency: Montana DPHHS Child Support Services Division (CSSD).
Estimate under Montana's child support guidelines effective February 1, 2026. Verified against the official Montana sources on October 7, 2026. Not legal advice. Courts can deviate from the guidelines. How we calculate →
By parenting time and the other parent's income
| Overnights | $0 | $20,000 | $30,000 | $40,000 | $50,000 | $60,000 | $80,000 | $100,000 |
|---|---|---|---|---|---|---|---|---|
| 0 | $886 A→B | $722 A→B | $626 A→B | $578 A→B | $544 A→B | $516 A→B | $462 A→B | $434 A→B |
| 52 | $886 A→B | $722 A→B | $626 A→B | $578 A→B | $544 A→B | $516 A→B | $462 A→B | $434 A→B |
| 104 | $886 A→B | $722 A→B | $626 A→B | $578 A→B | $544 A→B | $516 A→B | $462 A→B | $434 A→B |
| 128 | $752 A→B | $582 A→B | $470 A→B | $412 A→B | $366 A→B | $328 A→B | $244 A→B | $188 A→B |
| 182 | $354 A→B | $164 A→B | $2 A→B | $90 B→A | $168 B→A | $242 B→A | $414 B→A | $554 B→A |
The Montana worksheet for this example
| Line | Official label | Value |
|---|---|---|
| 1a (A) | Wages, salaries, commissionsParent A's annual gross income | $45,000.00 a year |
| 1a (B) | Wages, salaries, commissionsParent B's annual gross income | $40,000.00 a year |
| 1f (A) | Earned Income Tax Credit (EITC)Parent A's estimated earned income credit | $0.00 a year |
| 1f (B) | Earned Income Tax Credit (EITC)Parent B's estimated earned income credit | $3,923.00 a year |
| 1i (A) | Total income (add lines 1a–1h)Parent A's total income | $45,000.00 a year |
| 1i (B) | Total income (add lines 1a–1h)Parent B's total income | $43,923.00 a year |
| 2e (A) | Federal income taxParent A's estimated federal income tax | $3,220.00 a year |
| 2e (B) | Federal income taxParent B's estimated federal income tax | -$1,780.00 a year |
| 2f (A) | State income taxParent A's estimated Montana income tax | $1,358.00 a year |
| 2f (B) | State income taxParent B's estimated Montana income tax | $339.00 a year |
| 2g (A) | Social Security (FICA plus Medicare)Parent A's Social Security and Medicare | $3,443.00 a year |
| 2g (B) | Social Security (FICA plus Medicare)Parent B's Social Security and Medicare | $3,060.00 a year |
| 2l (A) | Total allowable deductions (add lines 2a–2k)Parent A's total deductions | $8,021.00 a year |
| 2l (B) | Total allowable deductions (add lines 2a–2k)Parent B's total deductions | $1,619.00 a year |
| 3 (A) | Income after deductions (line 1i minus 2l)Parent A's income after deductions | $36,979.00 a year |
| 3 (B) | Income after deductions (line 1i minus 2l)Parent B's income after deductions | $42,304.00 a year |
| 4 (A) | Personal allowance from policy 404.2 table 1Parent A's personal allowance | $20,748.00 a year |
| 4 (B) | Personal allowance from policy 404.2 table 1Parent B's personal allowance | $20,748.00 a year |
| 5 (A) | Income available for child support (line 3 minus line 4; if < 0, enter 0)Parent A's income available for support | $16,231.00 a year |
| 5 (B) | Income available for child support (line 3 minus line 4; if < 0, enter 0)Parent B's income available for support | $21,556.00 a year |
| 6 (A) | Minimum contribution (WS-C), or line 3 × 12% if line 5 > 0Parent A's minimum contribution | $4,437.00 a year |
| 6 (B) | Minimum contribution (WS-C), or line 3 × 12% if line 5 > 0Parent B's minimum contribution | $5,076.00 a year |
| 7 (A) | Compare each parent’s lines 5 & 6; enter higher numberParent A's income used for the shares | $16,231.00 a year |
| 7 (B) | Compare each parent’s lines 5 & 6; enter higher numberParent B's income used for the shares | $21,556.00 a year |
| 8 | Combined income available (add both columns, line 7)Combined income available | $37,787.00 a year |
| 9 (A) | Parental share of combined income (line 7 ÷ line 8)Parent A's share | 43% |
| 9 (B) | Parental share of combined income (line 7 ÷ line 8)Parent B's share | 57% |
| 11 | Primary child support allowance from policy 404.2 table 2Primary allowance for the children | $10,374.00 a year |
| 12a | Child care cost less dependent care tax creditChild care | $0.00 a year |
| 12b | Child health insurance premiumChildren's health insurance | $0.00 a year |
| 12c | Unreimbursed medical expense (> $250/child)Unreimbursed medical costs above the threshold | $0.00 a year |
| 12e | Total supplement (add lines 12a through 12d)Total supplements | $0.00 a year |
| 13 | Total primary allowance & supplement (add lines 11 & 12e)Children's total needs | $10,374.00 a year |
| 15 (A) | Parent’s share of total (line 13 × line 9)Parent A's share of the needs | $4,461.00 a year |
| 15 (B) | Parent’s share of total (line 13 × line 9)Parent B's share of the needs | $5,913.00 a year |
| 16 (A) | Compare line 15 to line 5; enter lower amountParent A's needs share, up to income available | $4,461.00 a year |
| 16 (B) | Compare line 15 to line 5; enter lower amountParent B's needs share, up to income available | $5,913.00 a year |
| 17 (A) | Income available for SOLA (line 5 minus line 16)Parent A's income available for SOLA | $11,770.00 a year |
| 17 (B) | Income available for SOLA (line 5 minus line 16)Parent B's income available for SOLA | $15,643.00 a year |
| WS-E | SOLA multiplierStandard of living adjustment factor | 21% |
| 20 (A) | SOLA amount (WS-E)Parent A's standard of living adjustment | $2,472.00 a year |
| 20 (B) | SOLA amount (WS-E)Parent B's standard of living adjustment | $3,285.00 a year |
| 21 (A) | Add line 16 and line 20Parent A's needs share plus SOLA | $6,933.00 a year |
| 21 (B) | Add line 16 and line 20Parent B's needs share plus SOLA | $9,198.00 a year |
| 22 (A) | Gross annual child support (higher of line 21 and line 6)Parent A's gross annual support | $6,933.00 a year |
| 22 (B) | Gross annual child support (higher of line 21 and line 6)Parent B's gross annual support | $9,198.00 a year |
| 24 (A) | Annual support per parent (line 22 minus line 23; if < 0, enter 0)Parent A's annual support | $6,933.00 a year |
| 24 (B) | Annual support per parent (line 22 minus line 23; if < 0, enter 0)Parent B's annual support | $9,198.00 a year |
| 25a (A) | Days with mother / with fatherDays a year with Parent A | 52 |
| 25a (B) | Days with mother / with fatherDays a year with Parent B | 313 |
| 25b / WS-B 12 | Support per child, per yearYearly support per child | $3,467.00 a year |
| 26b | Monthly support per child | $289.00 a month |
| 27 | Final monthly transfer paymentMonthly transfer payment | $578.00 a month |
Open the official Montana Child Support Guidelines Worksheets A–E →
With child care and health insurance
| Costs | Guideline amount |
|---|---|
| No add-ons | $578 a month A→B |
| Child care $500 a month | $748 a month A→B |
| Child care $1,000 a month | $918 a month A→B |
| Health insurance $150 a month | $628 a month A→B |
| Health insurance $300 a month | $680 a month A→B |
Child care, the children's health insurance and their recurring medical costs above $250 a child a year are added to the children's needs and shared by income; the parent who pays them gets credit. Child care is first reduced by the federal dependent care credit when the parent who claims the children pays it.
Things to know about this example
- Net income was estimated with Montana's standard assumptions (single filer, 2026 tax year). Your actual taxes may differ.
How Montana works it out
Montana uses a Melson-type formula on yearly amounts. Each parent keeps a personal allowance of $20,748. The children's primary allowance ($6,224 a year for one child) and their expenses are shared by the parents' incomes above the allowance; a standard of living adjustment then adds a share of each parent's remaining income.
Montana starts from total income, including the earned income credit and spousal support received, and subtracts income taxes, Social Security and Medicare, support ordered for other children, an allowance for other children at home and spousal support paid. Taxes here are estimated for a single filer. A parent with no income is treated as able to work full time at $10.85 an hour.
When the children spend more than 110 days a year with each parent, each parent's amount is reduced for the days above that number and the parent who owes more pays the difference.
Frequently asked questions
How much child support is paid on $45,000 in Montana for 2 children?
If Parent A earns $45,000 a year, Parent B earns $40,000 and the children live mostly with Parent B (52 overnights a year with Parent A), Montana's guideline amount is about $578 a month (Parent A pays Parent B).
How much is that a week?
That is about $133 a week (the monthly amount × 12 ÷ 52).
What if the parents share time equally?
With about equal parenting time and the same incomes, the guideline amount is about $90 a month (Parent B pays Parent A).
What if Parent B has no income?
If Parent B has no income and the children live mostly with Parent B, the guideline amount is about $886 a month (Parent A pays Parent B).
Official sources and verification
- Law: MCA 40-4-204, 40-5-209, 40-6-116; Admin. R. Mont. 37.62.101–37.62.148
- Montana child support guidelines
- Montana Child Support Guidelines Worksheets A–E
- Montana DPHHS Child Support Services Division (CSSD)
- Changing a Montana child support order
Guidelines effective February 1, 2026. Verified against the official Montana sources on October 7, 2026. How we calculate →