Various Adjustments of Tax Numbers for 2025

Filing statuses: S=single, HH=head of household, MFS=married filing separately, MFJ=married filing joint, QSS=qualifying surviving spouse

(MAGI mean modified adjusted gross income for that deduction.)
TCJA refers to the Tax Cuts and Jobs Act passed in 2017 which made major changes to many deductions/adjustments.
The 2025 tax bill "Public Law 119-21" made further changes, some retroactively for 2025 and others for future years.

Maximum Salary Deferrals: $23,500 for 401(k), 403(b), 501(c), 457 plans; / $16,500 for SIMPLE
'catch-up'contribution limits for age 50+*: additional $7,500 / $3,500 for SIMPLE
*'super-catch up' amount for ages 60-63: additional $11,250  / $5,250 for SIMPLE
Maximum contribution including any employer-matching: $70,000

$3,300 for Health FSA
$325/month transit benefits

Self-Employed: SEP-IRA: $70,000, with limitation of 20% adjusted net s/e income
Traditional IRA Contributions Limit: $7,000 (up to amount of earned income for the year)
  additional catch-up $1,000 for age 50+

Traditional IRA Deduction MAGI Phaseout:
(when also eligible to contribute
to a retirement plan at work)
MFJ, QSS:  $126,000-$146,000
S, HH:  $79,000-$89,000
MFS:  0-$10,000 (living apart all year, see S)
MFJ taxpayer when only other spouse covered by a plan: $236,000-$246,000

Roth IRA Contributions MAGI Phaseout:
MFJ, QSS:  $236,000-$246,000
S, HH:  $150,000-$165,000
MFS:  0-$10,000 (living apart all year, see S)

Retirement Savings Credit ('Saver's Credit')
Maximum AGI Limit:
MFJ:  $79,000
HH:  $59,250
S, QSS, MFS:  $39,500
Social Security: Before retirement age, can earn up to $23,400 without repaying benefits.
  Benefits reduced $1 for each $2 earned over limit
Preceding months in year of reaching retirement age: $62,160.
  Benefits reduced $1 for each $3 earned over limit
On/after retirement month, no earning limit.
Maximum monthly benefits for 2025: $5,108

Earnings subject to SS tax:
  Employee: $176,100 (maximum $10,918.20 w/h)
  Household help: cash wages over $2,800
Health Savings Account: Maximum HSA contribution $4,300 individual coverage / $8,550 family coverage.
  additional catch-up $1,000 for age 55+
Child Tax Credit: $2,200 per child under age 17, with up to $1700 potentially refundable.
  with phaseout starting at AGI of 400K MFJ, 200K others.
$500 credit for other dependents.
The refundable portion (additional child tax credit) now made a permanent part of the tax laws.
Child and Dependent Care Expenses/Credit: Allowed expenses for 20-35% credit on 3K for one child / 6K for two or more.
  Dependent care benefits set-aside 7.5K.
  Maximum credit $1,050 (one child) / $2,100 (two or more children) at 35% credit rate.
Educational Credit:  (MFS ineligible) American Opportunity Credit (aka Hope Credit):
  100% of first $2,000, 25% of next $2,000 tuition (all 4 years college)
   MAGI phaseout: $80,000-$90,000 (individual); $160,000-$180,000 (MFJ)
Lifetime Learning Credit: 20% of up to $10,000 tuition (any year college+)
   MAGI phaseout: $80,000-$90,000 (individual); $160,000-$180,000 (MFJ)
Student Loan Interest:  (MFS ineligible) Up to $2,500
MAGI phaseout: $85,000-$100,000 (individual); $170,000-$200,000 (MFJ)

Earned Income Credit:  (MFS ineligible)
Maximum Earned income/MAGI limit:
$19,104 (25-64 years old, no children), $50,434 (one child), $57,310 (two children), $61,555 (three children)
limits increased for MFJ by $7,110 (no children) else $7,120
Maximum credit will range from $649 for no children up to $8,046 for three or more children.
(disqualified if investment income over $11,950, any filing status)
Adoption Credit: Up to $17,280 (MAGI phaseout $259,190-$299,190)
Up to $5,000 can be refundable (2025 tax bill)
'Kiddie Tax' Child under 18/full-time student under 24, with interest/dividends over $2,700
That portion in excess of $2,700 is taxed at the parents' marginal (top) rate.
Standard Mileage Rates:   Business:  70¢  (Depreciation adjustment: 33¢)
  Charity:  14¢
  Medical:  21¢
Itemized Deduction phaseout: This had been eliminated (TCJA). But the 2025 tax bill brings it back starting in 2026 with a couple new phaseouts.
Itemized state and local tax deductions ('Salt' Limitation): This deduction had been capped at 10K (TCJA). The 2025 tax bill increased the cap to 40K, though the deduction is reduced by 30% of MAGI exceeding 500K (250K MFS) though not reduced below 10K.

In suceeding years through 2029, the deduction will increase annually another 1%. Without future tax law changes, will revert back to a 10K cap in 2030.
Section 179 Expense: total limit for tangible personal property placed in service: $2.5M (increased with 2025 tax bill)
phaseout starts at $4M placed in service
Depreciation Limit (with/without bonus depreciation): Passenger auto limit, first year business: $12,200 / $20,200
Capital Gain Tax: Long-term (holding over a year):

0% for taxable income up to $48,350K (S,MFS), $64,750K (HH), $96,700K (MFJ, QSS)
15% for next range of taxable income to $533,400 (S), $566,700 (HH), $600,050 (MFJ, QSS) or $300,000 (MFS)
20% for taxable income over those amounts.
Gift Tax Exclusion/ Estate Exclusion: $19,000 / $13.990M
Foreign Income Exclusion: $130,000