Retirement & Tax Planning Answers
How Is a FERS Annuity and TSP Taxed in Arizona?
Quick answer
Your FERS basic annuity is almost entirely taxable as ordinary income at the federal level. A small portion is a tax-free recovery of the contributions you already paid tax on during your career, calculated under the Simplified Method in IRS Publication 721 and recovered gradually over your life expectancy. Traditional TSP withdrawals are fully taxable ordinary income and are eventually forced by required minimum distributions. Qualified Roth TSP withdrawals are tax free, and Roth TSP no longer carries a required minimum distribution. In Arizona, that same income is taxed at a flat 2.5%, Social Security benefits are not taxed at all, and there is no estate or inheritance tax. Arizona also allows a subtraction of up to $2,500 per person per year for pension income from United States government service, and both spouses can claim it if both receive a qualifying federal pension. Be realistic about the scale of that: at a 2.5% rate, a full $2,500 subtraction saves roughly $63 a year.
The Simplified Method is the piece most federal retirees have never heard of. You contributed to FERS with money that was already taxed, so a slice of every annuity payment is a return of that basis rather than income. OPM reports the taxable amount, but the exclusion runs out once you have recovered your full contribution, at which point the annuity becomes fully taxable. Depending on hire date and FERS tier, employee contributions ran 0.8%, 3.1%, or 4.4% of salary, so for most retirees the excluded portion is small.
Traditional TSP is the larger tax problem for most federal households. It is fully ordinary income on withdrawal and it is eventually compelled by RMDs, which is why the years before RMDs begin carry so much planning value.
Arizona genuinely is friendly to retirees, and it is worth being precise about why rather than overselling it. The flat 2.5% rate, the full exemption of Social Security, and the absence of any estate or inheritance tax are the real benefits. The $2,500 federal pension subtraction is a rounding error by comparison.
The practical consequence is that state tax is not where a federal retirement plan is won or lost. Federal bracket management, conversion timing, IRMAA thresholds, and withdrawal sequencing move vastly more money than any Arizona-specific provision. Anyone selling an Arizona move primarily on the $2,500 subtraction is not doing the arithmetic.
Withholding is its own trap. OPM withholding on the annuity and TSP withholding on withdrawals are set separately and neither knows about the other, so federal retirees frequently arrive at April with a balance due or an underpayment penalty despite having had tax withheld all year.
Treat Arizona's tax treatment as a modest tailwind, not a strategy. The federal side is where the money is.
If you moved to Arizona from a higher-tax state, the savings are real, but they are driven by the flat 2.5% rate and the Social Security exemption, not the pension subtraction.
Check your combined withholding across the annuity and the TSP at least once a year rather than assuming the defaults are right.
- Assuming the FERS annuity is largely tax free because you contributed to it. Only a small portion is excluded.
- Overestimating the Arizona federal pension subtraction, which is capped at $2,500 per person and worth about $63 at the state rate.
- Forgetting that Roth TSP no longer has a required minimum distribution, which changes withdrawal order.
- Setting OPM and TSP withholding independently and discovering the shortfall at filing time.
- Relocating to Arizona for tax reasons without modeling the federal bracket and IRMAA effects that dwarf the state result.