Why Your Default GRB Report Understates Your Pension

If you've downloaded a retirement estimate from the GRB portal lately, there's a good chance the number you saw was too low — possibly by a lot. Not because the math is broken, but because of what the default GRB report assumes. That standard PDF — the one most officers pull, file, and anchor their expectations on — computes your future annuity on your current high-3 salary. Your grade and step today, frozen for the rest of your career.

Think about what that means. Your FSPS annuity is a percentage of the average of your highest 36 months of basic pay — for almost everyone, the last three years before retirement. If you're an FS-03 today planning to retire in twenty years, your pension won't be based on FS-03 pay; it will be based on whatever grade and step you finish at. The default report gives you a full career's worth of service years priced at today's salary. For someone retiring next year, that's a fine approximation. For a mid-career officer — let alone a first- or second-tour officer — it can understate the real number by a third or more.

To be fair, the GRB platform also includes an interactive retirement calculator that lets you set your retirement year and your own estimated high-3 — and used that way, with realistic inputs, it produces a sound estimate. But the default report is what officers are asked for, what they file, and what they anchor on. And the default report answers a question nobody asked: what would my pension be if I never got promoted again?

This isn't unique to the Foreign Service, by the way. The same current-high-3 assumption sits inside estimates for FERS employees across the government. But Foreign Service careers, with their structured grade progression and the FSPS 50-and-20 retirement pattern, make the gap unusually visible — so let's put real numbers on it.

A worked example

Take an FS-03 at step 7 in 2026. Base schedule pay is $99,085. For FSPS annuity purposes, overseas or domestic, the high-3 basis credits the Washington, DC locality rate — 33.94% this year — so today's annuity basis is about $132,700.

Suppose this officer joined at 26, plans to retire at 50 with 24 years of service, and — nothing heroic here — finishes the career as an FS-01. The default GRB report projects the full 24 years of service but prices them on today's $132,700 basis: with the FSPS multiplier of 1.7% for the first twenty years plus 1.0% for each year after, 24 years earns 38% of high-3, or about $50,400 per year.

Now run the same career priced at the finish line instead of the starting blocks. An FS-01 in the upper steps tops out the base schedule at $164,301, and with the DC rate applied, the annuity basis hits the Executive Level IV pay ceiling of $197,200. The same 38% multiplier on that basis produces roughly $74,900 per year.

Same officer, same career, same retirement date. One method says $50,400; the other says $74,900. The default figure understates the realistic pension by about a third — roughly $24,500 a year, every year, for life. For an officer deciding whether the Foreign Service is worth staying in, that's not a rounding error. That's the difference between a pension that sounds thin and one that anchors a retirement.

The honest way to think about future dollars

A fair objection: nobody knows what pay tables will look like in 2048, so isn't projecting a future grade just a different kind of guessing? Here's the distinction. Pricing your expected retirement grade on today's pay table tells you your pension in today's purchasing power — a conservative, meaningful number, because federal pay scales and the FSPS cost-of-living adjustment both track inflation over long horizons, imperfectly but persistently. Pricing your current grade on today's table, as the default report does, answers a question nobody asked: what would my pension be if I never got promoted again and retired the way I am now?

The first number is a planning tool. The second is a snapshot mislabeled as a forecast.

What to do with this

If you're within a couple of years of retirement, relax — the default GRB report is close, because your current grade and your final grade are the same thing. The younger you are, the more skeptical you should be, and the more the estimate functions as a floor rather than a projection.

When you run your own numbers, use the grade and step you realistically expect to hold at retirement, priced in today's dollars, and treat the result as purchasing power rather than a future paycheck. That's exactly how our free Foreign Service Retirement Benefits Calculator is built — it asks for your grade and step at retirement, works from the official 2026 pay schedules, shows every step of the arithmetic, and tells you plainly when a figure is in today's dollars. You can run your own scenario in about two minutes at tools.carringtonfp.com.

And if the number you get changes how you're thinking about your career — in either direction — that's usually the moment the conversation is worth having with a planner who knows how the Foreign Service actually works.

William Carrington, CFP®, RMA®, is the principal of Carrington Financial Planning LLC, a fee-only fiduciary firm serving U.S. Foreign Service families. Figures use the official 2026 Foreign Service Salary Schedules (effective January 11, 2026) and are estimates for planning discussion, not advice.