2025 Form 1040, Lines 6a & 6b
Social Security Benefits: Lines 6a/6b and §86
2025 Form 1040, Lines 6a/6b — gross benefits from SSA-1099 Box 5 go on 6a; the taxable slice lands on 6b. Provisional income decides the slice: 0%, up to 50%, or up to 85% taxable under IRC §86 — see Guide Ch. 2.
Provisional income runs the table
AGI plus tax-exempt interest plus half your benefits. Under $25,000 single / $32,000 joint: none taxed. Between the tiers: up to 50%. Over $34,000 / $44,000: up to 85%. Muni interest counts here even though it is exempt everywhere else — the classic trap.
W-4V: withholding from benefits
Form W-4V elects 7%, 10%, 12%, or 22% federal withholding from each payment. If part of your benefits are taxable and nothing is withheld, this is the clean fix for next April's surprise.
Questions, answered
- What is provisional income?
- AGI plus tax-exempt interest plus half your Social Security benefits. Under $25k single / $32k joint, benefits aren't taxed; above the second tier ($34k/$44k), up to 85% is.
- Can I have withholding taken from benefits?
- Yes — Form W-4V elects 7%, 10%, 12%, or 22% federal withholding from each payment. The clean fix for an April surprise.
- Does working while collecting change this?
- Earnings can reduce benefits before full retirement age (SSA earnings test) and raise provisional income, pushing more benefits into tax. Two separate bites.
Keep reading: Total Income (Line 9) · Taxable Income (Line 15) · Refund or Owed