Updated July 28, 2026. Quick answer: Probably not — but Mississippi is one of the two states where the usual shortcut is genuinely risky. Retirement income is broadly exempt, but the exemption is written around distributions taken under the plan’s normal terms, and a conversion is not one. The cited authority does not address conversions directly.
Confidence note: the authority cited below is clear about retirement distributions and silent about conversions specifically. That silence is the finding, not an oversight in our research.
Why a conversion is a different question from a withdrawal
Almost every state summary answers “how does Mississippi tax retirement income?” That is a question about distributions. A Roth conversion is not a distribution in the ordinary sense — it is a voluntary election to recognise income now in exchange for tax-free growth later. Whether a state’s retirement exclusion reaches that election is a separate question, and it is the one that decides your bill.
This is the distinction almost every summary misses. “Retirement income is exempt in Mississippi” is a true statement about distributions. A Roth conversion is not a distribution taken at normal retirement — it is an election to move money between accounts and recognise income now.
We are not going to tell you the exemption definitely applies, because the authority we can cite does not say that. What we can tell you is exactly where the ambiguity sits, so you can put a specific question to a preparer instead of a vague one: does the Mississippi retirement exclusion reach a conversion, or only a distribution taken under plan terms?
What Mississippi does with the converted amount
State income tax: flat 4% for 2026 (final cut under prior schedule; HB 1 of 2025 continues: 3.75% in 2027, then -0.25%/yr to 3% by 2030, with growth triggers toward elimination). First $10,000 of taxable income exempt.
How Mississippi treats IRA and plan income: Fully exempt: all qualified retirement income — pensions (public/private), 401(k)/403(b), IRA distributions taken per plan terms (normal retirement), annuities. Early/non-qualified distributions are taxable.
What to ask a preparer about Mississippi
Does the retirement exclusion reach a Roth conversion, or only a distribution taken under the plan’s normal terms? Ask it in exactly those words — a general “is retirement income taxed here” will get you the wrong answer.
Converting around a move
Converting in the year you move into Mississippi is the case that catches people. Residency at the moment of conversion is what generally determines which state gets to tax it, so a conversion executed a week before a move and one executed a week after can produce different bills.
Four separate taxes change when you move, not one: income tax on withdrawals, treatment of Social Security, estate tax, and inheritance tax. A state that looks good on conversions can be worse on the other three.
The state bill is the smaller half
Whatever Mississippi does, the conversion is federal ordinary income first. The federal bracket you land in, and whether the conversion pushes you over an IRMAA threshold two years later, will usually move more money than the state line does. The state answer tells you whether to convert here; the federal answer tells you how much to convert at once.
Paying the tax from outside the account matters more than either. Using converted dollars to pay the bill shrinks the balance that was the entire point of converting.
Sources
Authority: Miss. Code § 27-7-15(4)(k) (retirement income exclusion); HB 1 (2025), ‘Build Up Mississippi Act’.
Compiled from state statutes, session laws and revenue-department publications and adversarially verified in July 2026. Dataset confidence for Mississippi: high.
This page states what the cited authority says. It is not tax advice, and a conversion large enough to matter is worth putting in front of a preparer who can see your whole return.