Delaying Social Security to 70: when the 24% reaches your check

Each month you wait past full retirement age (FRA) adds two-thirds of 1% to your Social Security retirement benefit, which works out to 8% a year, and the increase stops at age 70 (SSA delayed retirement credits). For workers born from 1960 on, waiting the full stretch pays 24% more than your FRA amount for life.

How much of that applies to you depends on your birth year, the benefit in question and the month you file. The credits also reach your bank account on a calendar set by federal regulation, and a late application after 70 can cost months of payments outright.

24% for anyone born in 1960 or later

Birth year decides how many credit months are still open to you. Credits build from your FRA month through the month you turn 70, so an earlier FRA leaves a longer runway.

FRA by birth year from the SSA retirement age chart, which counts a January 1 birthday as the previous year. Increases are months × two-thirds of 1% under 20 CFR 404.313.

People born in 1955 or earlier have already passed 70.

The percentage multiplies your primary insurance amount (PIA), the monthly figure your earnings record produces at FRA. Your PIA also picks up each cost-of-living adjustment (COLA) from the year you turn 62, whether you’ve filed or not (how your primary insurance amount is calculated), so those raises are already built in when you finally claim.

Which benefits grow while you wait

Only two of the payments made on your record get bigger when you delay: your own retirement benefit and the benefit a surviving spouse may receive after your death.

Source: paragraphs (d) and (e) of the federal credit regulation.

Your spouse’s benefit never includes your credits, so your waiting until 70 leaves it exactly where it was.

Credits you earn feed into the survivor benefit even if you die before you ever file. They’re added to a surviving spouse’s benefit before the family maximum is applied, while for your own benefit they’re added after it.

Why is my first check smaller than the calculator said?

Take a single worker born in mid-June 1960 with a PIA of $2,400 a month, reaching FRA in June 2027. COLAs are left out so only the credits show.

SSA’s planner page warns that some credits aren’t applied until the January after benefits start. Three timing rules decide which credits land where (20 CFR 404.313(c)). Credits earned before your filing year go into your first payment. Credits earned during the filing year wait for the following January. Age 70 is the exception: credits from that calendar year are added in the birthday month itself.

Example:

Single worker, PIA $2,400, born mid-June 1960, COLAs excluded.

Starting at 69, the payments for June through December 2029 each run $80 below the full-credit amount. The five credits from January to May 2029 only arrive in January 2030, when the benefit rises to $2,784.

Each increase is rounded down to the next 10 cents, and the final payment is rounded down to the next whole dollar after any Medicare premium comes out. To rerun the example with your own numbers, enter your birth year and PIA, then try claiming ages of 69 and 70, in the Social Security calculator.

A start at 70 puts all 36 credits into the very first payment.

Filing after 70 costs months you can’t get back

Six months is as far back as SSA will pay, and it never pays for any month before you reached FRA (SSA’s back-pay rule).

Before 70, each month of back pay is a month that would otherwise have earned a credit. Asking for six months of back pay at 69 gives up six credits, which is 4% of your PIA. On the $2,400 example that’s $96 a month less for as long as benefits are paid.

After 70, no credits are left to lose, so back pay up to the six-month limit costs nothing. The worker from the example reaches 70 in June 2030. Applying in March 2031, the earliest payable month is September 2030, and the payments for June, July and August 2030 are gone: 3 × $2,976 = $8,928.

Deadline: Apply no later than six months after your 70th-birthday month, and every month back to that birthday month can still be paid.

Before you agree to a start date, ask the Social Security claims representative: “Which month will my benefit start, and does that month cost me any delayed retirement credits?”

Can you earn credits after claiming early?

If you started benefits at 62 or 64, you can still collect credits by asking SSA to suspend your payments once you reach FRA (SSA voluntary suspension).

Suspension begins the month after you ask. Payments restart on their own at age 70 unless you ask to restart sooner.

The costs fall on other people and other programs. Anyone paid on your record stops receiving benefits for the same months, Medicare premiums can no longer come out of the suspended payment, and SSI recipients lose SSI eligibility while suspended.

Within 12 months of first claiming there’s a second route: you can withdraw your Social Security application and repay what you received.

Medicare at 65 and the HSA months you lose

SSA tells people who put off retirement benefits past 65 to apply for Medicare within 3 months of their 65th birthday anyway, because Part B and Part D can cost more if they wait (SSA retirement age chart).

Workers still putting money into a health savings account have one more date to track. Applying for Social Security after 65 also enrolls you in Medicare Part A, and that coverage can be backdated up to six months, never earlier than your 65th birthday (HSA and Medicare rules).

IRS Publication 969 sets your HSA contribution limit at zero from the first month you’re enrolled in Medicare, and it applies that rule to backdated months as well (IRS Publication 969). Money that went in during those months is an excess contribution, taxed at 6% for each year it stays in the account. You avoid that tax by withdrawing the excess and its earnings by your return’s due date, including extensions.

Before you sign: A Social Security application filed after 65 brings Part A with it. End HSA contributions, both yours and your employer’s, before the backdated months begin.

Ask a CPA or enrolled agent: “Given the month I’ll apply for Social Security, which month will my Part A start, and what is my prorated HSA limit for that year?”

Choose age 70 as your benefit start month

Mark your 70th-birthday month first, then work backward from it.

1. Check your FRA and credit months in the birth-year table above.
2. If you or your employer fund an HSA, stop those contributions six months before you plan to apply.
3. Apply for retirement benefits and name that birthday month as the first month of benefits.
4. When the award letter arrives, compare the monthly amount with your PIA plus the percentage in the table. Credits earned during that final calendar year should already be in it.

If you plan to cover the years before 70 from an IRA or 401(k), take that plan to a fee-only fiduciary planner and ask: “If I fund the years until 70 from my IRA or 401(k), how does that change my taxable income and my Medicare premium tier in each of those years?”