These 4 credit unions offer outstanding APYs on savings — and anyone can join

Banking with a credit union can come with perks. Credit unions often offer lower rates on credit and loan products, reduced fees and higher interest rates on deposits — including savings accounts.

CNBC Select compiled a list of the best savings accounts offered by credit unions. We picked the accounts that offer high interest rates, charge no monthly fees and require low or no minimum balance. We also made sure to only include credit unions that are easy to join and insured by the National Credit Union Administration (NCUA). (Read more about our methodology below.)

Who's this for? Whether you're looking for a savings account for a small rainy day fund or to hold larger sums of money, the Quorum Federal Credit Union HighQ Savings Account can be an excellent choice.

HighQ Savings consistently offers generous APY on any balance and makes it easy to maintain your account. As long as you opt-in to receive electronic statements, you won't incur any monthly fees (there is a $10 monthly fee if you choose to receive paper statements). There are also no minimum deposit or balance requirements to worry about.

If you also get a checking account with Quorum, you'll have access to more than 90,000 fee-free ATMs nationwide.

To open an account with Quorum, you'll first need to join the credit union. You can join if you or someone in your household works for or retired from an eligible SEG company. Alternatively, you qualify for a membership if you join American Consumer Council (ACC) or Select Savers Club (SSC). Joining ACC is free and signing up for SSC costs $5 — which Quorum will pay for you.

Who's this for? If the idea of putting down a sizeable deposit (namely, $1,000) doesn't put you off, Ultra Savings from KeyPoint Credit Union can offer you an outstanding interest rate.

As of writing, Ultra Savings earns 4.85% APY, regardless of your account balance. You need a $1,000 minimum deposit to open an account but after that, you don't have to maintain any balance to keep it. Plus, KeyPoint doesn't charge any monthly fees.

You can get an ATM card for your savings account and use KeyPoint's locator to find your closest ATM.

You can join the credit union seamlessly while signing up for Ultra Savings. As one of the options, you'll be prompted to enroll with The Financial Fitness Association (FFA) — and KeyPoint will pay the $8 membership fee for the first year. You're also qualified to join if you live or work in one of the eligible counties in California, work for a member company or are an immediate family of an existing member.

Who's this for? If you'd rather not fork out a large deposit to take advantage of a high interest rate on your savings, SmartStart Savings from Affinity Federal Credit Union can be another great option.

SmartStart offers 4% APY as of writing on the first $10,000 in your account and 1% thereafter. The cap is not ideal but shouldn't deter an average saver. According to the most recent Federal Reserve's Survey of Consumer Finances (SCF), Americans have a median transaction account balance of $5,300 — well below Affinity's limit.

Affinity charges no account fees on SmartSavings and requires no minimum balance. However, if you choose to receive paper statements, you'll have to pay a $2 monthly fee.

If you automate your savings and set up direct deposits from your paycheck, you can receive the funds up to two days early in your SmartSavings account.

Joining Affinity is easy — you can do it in-branch, over the phone or online. All it takes is a $5 membership deposit which will be held in a separate Membership Eligibility Account.

Who's this for? If you're only planning to hold a small amount in your savings account, Digital Federal Credit Union (DCU) Primary Savings can yield generous returns.

Primary Savings currently offers a 6.17% APY on up to $1,000 and 0.16% to 6.17% thereafter. If you reach the cap, it might be wise to open another savings account to continue earning high returns.

You only need $5 to open and retain an account. There are no monthly fees. You can also get an ATM card and use it at any DCU or CO-OP ATM across the U.S.

You're eligible to join the credit union and open this account if you're a relative of a current DCU member, work for or are retired from one of DCU's participating employers or live, work, study or worship in one of DCU's communities. Alternatively, you can join one of the participating organizations DCU works with. The most affordable option here is the non-profit organization Reach Out for Schools, which offers memberships starting at $10.

Savings accounts at credit unions can offer excellent interest rates and low account fees (or none at all). Make sure to consider several accounts to find one that works best for you. And remember: You don't have to keep your savings in a single account. You can always open additional accounts, whether to avoid a cap when chasing a high APY or to compartmentalize your savings goals.

At CNBC Select, our mission is to provide our readers with high-quality service journalism and comprehensive consumer advice so they can make informed decisions with their money. Every credit union review is based on rigorous reporting by our team of expert writers and editors with extensive knowledge of credit union products. While CNBC Select earns a commission from affiliate partners on many offers and links, we create all our content without input from our commercial team or any outside third parties, and we pride ourselves on our journalistic standards and ethics. See our methodology for more information on how we choose the best credit unions.

To determine which credit union savings accounts offer the best return on your money, CNBC Select analyzed dozens of U.S. savings accounts offered by credit unions. We narrowed down our ranking by only considering those savings accounts that offer an above-average APY, no monthly maintenance fees and low (or no) minimum balance requirements. We also only included credit unions that anyone can join.

While the accounts we chose in this article consistently rank as having some of the highest APY rates, we also compared each saving account on a range of features, including ease of use and account accessibility, as well as factors such as insurance policies and customer reviews when available. We also considered users' deposit options and each account's compound frequency.

All of the accounts included on this list are NCUA-insured up to $250,000. Note that the rates and fee structures for savings accounts are not guaranteed forever; they are subject to change without notice and they often fluctuate in accordance with the Fed rate. Your earnings depend on any associated fees and the balance you have in your high-yield savings account. To open an account, most institutions require a deposit of new money, meaning you can't transfer the money you already had in an account at that bank.

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