Navy Federal Credit Union pays 0.25% APY on its basic Share Savings Account and 4.10% APY on an 18-month certificate opened with $1,000, a spread of 3.85 percentage points inside one institution. Both figures come from the credit union’s published rate sheet, which read “Rates as of Sep 30, 2026 ET” when it was re-read for this article. The gap shows how much an older saver’s choice of account matters at a single credit union.
The rate sheet from top to bottom
The Share Savings Account requires a $5.00 minimum deposit and pays 0.25% APY. The Money Market Savings Account pays by balance tier: 0.00% on $0 to $2,499, 1.00% on $2,500 to $9,999, 1.10% on $10,000 to $24,999, 1.15% on $25,000 to $49,999 and 1.55% at $50,000 and above. A money market balance under $2,500 therefore earns nothing at the posted rate, and the top tier still pays far less than a mid-length certificate.
Certificates are listed at two minimums, $1,000 and $100,000. The sheet shows 1.50% and 1.55% for three months, 4.05% and 4.10% for 12 months, 4.10% and 4.15% for 18 months, 3.66% and 3.70% for 24 months, 4.10% and 4.15% for three years, 3.85% and 3.90% for five years and 3.85% and 3.90% for seven years. The 4.10% in the headline is the $1,000 tier of the 18-month term; the 4.15% figure needs $100,000. The footnote states that dividends are “compounded daily, credited monthly.”
The shape is unusual. The 12-month, 18-month and three-year certificates sit at or near the top of the ladder, the 24-month term dips to 3.66%, and the five- and seven-year terms pay less than the 18-month one. On this sheet a longer commitment does not buy a higher rate.
What the spread is worth on a $10,000 balance
The arithmetic is straightforward. At 0.25% APY, $10,000 in Share Savings earns about $25 over a year. At 4.10% APY, $10,000 in the 18-month certificate earns about $410 over a year of that term, before taxes. The difference is roughly $385 a year for the same principal. In the money market account, the same $10,000 sits in the 1.10% tier, about $110 a year, which lands between the two.
The certificate rate applies only if the money can stay put for the full 18 months, which is the tradeoff between the two products. Share Savings has no term and the certificate is an 18-month commitment, so the two are not direct substitutes, and the rate sheet does not by itself say which suits a particular saver’s cash needs.
A middle option at an online bank
The credit union’s 0.25% is not the only savings benchmark. Ally Bank’s Online Savings Account listed 3.1% APY “correct as of 09/29/26,” with a $0 minimum opening deposit and $0 monthly maintenance fees. That is a flexible-access account at a rate far above Navy Federal’s basic savings and about a full point under its 18-month certificate. Ally states that deposits are insured by the FDIC up to the maximum allowed by law.
Online savings rates change without notice, and a rate quoted on one day may not hold for the next. The Ally figure carries its own date for that reason, and the Navy Federal figures carry theirs.
Who can open an account at Navy Federal
The rates are not open to every saver. Navy Federal’s membership page lists active-duty members of the Army, Marine Corps, Navy, Air Force, Coast Guard, National Guard and Space Force, veterans “no matter how long you served,” Department of Defense civilians including “employees, contractors, retirees and annuitants,” and immediate family members including “spouses, siblings, parents, children, grandparents and grandchildren.” The page adds that eligibility extends to households of current members and to families of deceased servicemembers and veterans on submission of documentation such as a DD-214.
The credit union’s own rate sheet describes the field of membership as “open to the armed forces, the DoD, veterans and their families.”
Insurance and the tax on the interest
A credit union’s deposits are insured by a different federal agency than a bank’s. The National Credit Union Administration says on its share insurance page that its fund “insures individual accounts at federally insured credit union up to $250,000,” and that “a member’s interest in all joint accounts combined is insured up to $250,000.” The agency also states that the fund is “backed by the full faith and credit of the United States.”
Interest is taxable income whatever the account is called. The Internal Revenue Service says in Topic No. 403 that “most interest that you receive or that is credited to an account that you can withdraw from without penalty is taxable income in the year it becomes available to you,” and it lists “dividends on deposits or on share accounts in cooperative banks, credit unions” among distributions that count as taxable interest. A Form 1099-INT is expected at $10 or more, but the IRS says all interest must be reported “even if you don’t receive a Form 1099-INT.”
The figures above are Navy Federal’s posted rates as of Sept. 30, 2026 ET and Ally’s as of 09/29/26. Both institutions can change them, and the credit union’s rate sheet is the controlling record for every Navy Federal number in this article.
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This article was produced with AI assistance and checked against the primary sources linked above.
Warren Cohen is a finance writer based in Phoenix, Arizona, covering personal finance topics including credit, banking, and beginner investing. He earned his degree in business administration from Arizona State University and began his career working in consumer finance, where he gained direct experience with lending and credit systems. He now writes for personal finance websites and fintech platforms, focusing on clear, practical content that helps readers make informed financial decisions.
