How much purchasing power does the diet COLA cost over time?

It depends on inflation, but the effect compounds because each year's smaller adjustment is applied to a lower base, so the gap versus a full COLA widens every year. Over a typical 20 to 25-year retirement, the FERS cap can reduce purchasing power by roughly 15 to 20 percent compared with a CSRS retiree who receives the full COLA on the same pension. On a $40,000 annuity, even a single year's one-point shortfall is $400 — and that shortfall repeats and grows for the rest of your life.

How do I protect my retirement from the diet COLA?

Three moves help. First, treat your TSP as your inflation hedge: the C, S, and I funds can grow with or ahead of inflation, unlike your capped annuity, so building a larger balance gives you a source of income that keeps pace. Second, consider delaying Social Security toward age 70, because Social Security receives the full CPI-W COLA with no cap, and delaying grows a larger base that then gets that full adjustment. Third, plan deliberately for any years before age 62, when your pension receives no COLA at all, by leaning on TSP or other savings during that window.

Retirement Savings Inflation

The inflation mistake that quietly erodes a 30-year federal retirement

Q: Does a FERS pension keep up with inflation?

Only partially. FERS annuities receive a cost-of-living adjustment, but it is a reduced 'diet COLA' whenever inflation runs above 2 percent. If the CPI-W rises 2 percent or less, FERS gets the full amount. If it rises between 2 and 3 percent, the FERS COLA is capped at 2 percent. If it rises above 3 percent, the FERS COLA equals CPI-W minus one percentage point. CSRS pensions and Social Security, by contrast, always receive the full CPI-W increase. Over a long retirement, that gap compounds into a meaningful loss of purchasing power.

Q: Why don't FERS retirees under 62 get a COLA?

By law, most non-disabled FERS retirees receive no cost-of-living adjustment at all until they reach age 62. If you retire at your minimum retirement age under the MRA+10 or MRA+30 provisions, your annuity stays flat — no inflation adjustment — until 62. Exceptions apply to disability retirees, survivor annuitants, and special-category employees such as law enforcement officers, firefighters, and air traffic controllers. This waiting period matters because inflation erodes your starting base before the diet COLA even begins.

Q: What is the 2026 FERS COLA?

For 2026, the CPI-W rose 2.8 percent, which lands in the middle bracket of the FERS formula. So CSRS retirees and Social Security recipients receive the full 2.8 percent, while eligible FERS retirees receive 2.0 percent — an eight-tenths-of-a-point haircut in a single year. The 2027 adjustment is tracking higher, which under the FERS formula would produce an even larger gap.

Most federal employees plan as if their pension will keep pace with inflation. It won’t — not fully. The FERS “diet COLA” trims your raise whenever inflation runs hot, and the shortfall compounds silently for decades. Here’s exactly how the erosion works, and the three moves that fight back.

By Anshul Meena • Published July 25, 2026 • 8 min read

2.0%

2026 FERS COLA vs. 2.8% for CSRS and Social Security

OPM 2026

CPI −1

Your COLA when inflation runs above 3%

FERS formula

COLA most FERS retirees get before age 62

The gap

15–20%

Purchasing-power loss over 20–25 years vs. a full COLA

Est.

1. The mistake hiding in your plan

Ask most federal employees whether their pension is inflation-protected and they’ll say yes — it gets a COLA, after all. That answer is only half right, and the missing half quietly costs a fortune over a long retirement.

The FERS pension does get an annual cost-of-living adjustment, but it’s a reduced one whenever inflation runs above 2%. CSRS retirees and Social Security recipients get the full inflation figure; FERS retirees get less. Plan as if your pension keeps full pace with prices, and you’ll overestimate your future buying power — by more, every single year.

2. How the diet COLA actually works

The formula has three brackets, keyed to the CPI-W inflation figure OPM uses each year:

The FERS “diet COLA” formula
If CPI-W inflation is…	CSRS & Social Security get	FERS gets
2% or less	The full increase	The full increase
Between 2% and 3%	The full increase	Capped at 2%
More than 3%	The full increase	CPI-W minus 1 point

You only get the full COLA in the years inflation is tame. Precisely when inflation bites hardest — above 3% — your protection is weakest, because you lose a full point off the top. In 2026, CPI-W came in at 2.8%, so CSRS and Social Security got 2.8% while FERS retirees got 2.0%. That eight-tenths-of-a-point gap opened up in a single, fairly ordinary year.

3. The under-62 gap that makes it worse

There’s a second, sharper edge. Most non-disabled FERS retirees receive no COLA at all until age 62. If you retire at your minimum retirement age under MRA+10 or MRA+30, your annuity simply stays flat — no inflation adjustment — until the year you turn 62.

Retire at 57 and that’s potentially five years of frozen income while prices keep climbing. Your starting base is already eroded before the diet COLA even switches on. (Disability retirees, survivor annuitants, and special-category employees — law enforcement, firefighters, air traffic controllers — are exceptions and get COLAs earlier.)

Two hits, not one

An early FERS retiree can take both hits at once: years of zero COLA before 62, then a diet COLA for the rest of retirement. Together they can carve a serious hole in purchasing power over 30 years.

4. How a small shortfall compounds

A one-point COLA gap sounds trivial. It isn’t, because of how it compounds: each year’s smaller adjustment is applied to a lower base, so the gap against a full-COLA pension doesn’t just repeat — it widens, every year, for life.

On a $40,000 pension, a single year’s one-point shortfall is $400. The problem isn’t that year — it’s that the $400 gap becomes the new baseline, and next year’s gap is measured from there. Compounded over decades, it’s real money.

Across a typical 20-to-25-year retirement, the cap can cut a FERS retiree’s purchasing power by roughly 15 to 20% compared with a CSRS retiree drawing the same pension. The higher your annuity and the longer you live, the larger the dollar gap grows.

5. Why it exists — and the bill to end it

The diet COLA wasn’t an accident. When FERS was designed, the logic was that FERS retirees also receive Social Security (which gets the full COLA) and a TSP (which can grow with inflation), so the pension’s own adjustment could be trimmed without leaving retirees unprotected. That’s the theory — and it means your other two income legs are supposed to carry the inflation load the pension doesn’t.

There’s a standing effort to change it: the Equal COLA Act (H.R. 491 / S. 624) would remove the FERS cap and give FERS retirees the same full COLA as CSRS and Social Security. It has been introduced in multiple Congresses. As of mid-2026 it is not law, so plan around the current rules, not the hoped-for ones.

6. The three moves that fight back

You can’t change the formula, but you can build a retirement that doesn’t depend on it. Three moves do most of the work:

Fighting the diet COLA
Move	Why it works
1 Build the TSP as your inflation hedge	Unlike your capped annuity, the C, S, and I funds can grow with — or ahead of — inflation. A larger balance gives you income that keeps pace where the pension can’t.
2 Consider delaying Social Security	Social Security gets the full CPI-W COLA, no cap. Delaying toward 70 grows a bigger base that then receives that full inflation adjustment for life — a powerful, uncapped hedge.
3 Plan the under-62 window	If you’ll retire before 62, budget for years of no pension COLA. Lean on TSP or other savings during that stretch so a flat annuity doesn’t force a lifestyle cut.

The reframe

The diet COLA isn’t a reason to panic — it’s a reason to lean on the two legs built to carry inflation. Your pension is the stable floor; your TSP and Social Security are the parts that grow. Fund and time them accordingly.

7. FAQ

Does a FERS pension keep up with inflation?

Only partially. FERS gets the full COLA when CPI-W is 2% or less, a capped 2% when inflation is 2–3%, and CPI-W minus one point when inflation exceeds 3%. CSRS and Social Security always get the full increase. Over a long retirement the gap compounds.

Why don't FERS retirees under 62 get a COLA?

By law, most non-disabled FERS retirees get no COLA until 62. Retire at your MRA under MRA+10 or MRA+30 and your annuity stays flat until then. Disability retirees, survivors, and special-category employees are exceptions.

How much does the diet COLA cost over time?

It compounds, because each smaller adjustment applies to a lower base. Over 20–25 years the cap can cut purchasing power 15–20% versus a full COLA on the same pension. On a $40,000 annuity, a single year’s one-point shortfall is $400 — and it repeats and grows.

What is the 2026 FERS COLA?

CPI-W rose 2.8% for 2026, so CSRS and Social Security got 2.8% while eligible FERS retirees got 2.0% — an eight-tenths-of-a-point haircut in one year. The 2027 figure is tracking higher, which would widen the gap.

How do I protect against it?

Build the TSP (C/S/I funds grow with inflation), consider delaying Social Security toward 70 (full, uncapped COLA on a bigger base), and budget for the no-COLA years before 62 by leaning on savings.

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