This is a guest-post from long-time reader MikeVx.

For many people, access to automatic teller machines (ATMs) is an important factor when choosing a financial institution. With the growth of the Co-Op Network of ATMs, most credit union members now have access to more no-cost ATMs than any several large banks put together.

If your credit union is a member of the Co-Op network, you have surcharge-free access to most of the credit union ATMs in the country for withdrawals, plus a good number of others located in various places. The Co-Op Network website provides an ATM locator. Input a ZIP code of interest, and the site will list ATMs in the area.

As an example, when I input my home ZIP code in southeast Michigan, I get 100 ATMs within 8 miles of my home. I think it stops at 100 locations or 10 miles. Of the 100 locations I get, about 55 can take deposits. As my CU is headquartered in Minnesota and the nearest branch is by the airport 15 miles away, this is very useful. Also, I am close enough to the border that my results include a couple of locations in Canada. I have yet to try a Canadian Co-Op terminal, so I don’t know what the conversions might be like.

There are a number of no-deposit terminals in unlikely places. Gas stations, bowling alleys, and convenience stores. Some time last year, the ATM Axis, which runs the ATMs for all of the 7-Eleven stores I am aware of, joined the Co-Op Network. Except for some of the larger deserts, it is difficult to be more than 10 miles from a 7-Eleven in the US. If you need cash, you can usually get it. As a personal example: I was in Chicago last year, and spent a bit more than I’d planned. Getting extra cash was as simple as visiting a 7-Eleven that I remembered from the previous year at this event.

One drawback to the use of the network: Depending on the policy of your credit union, deposits made to network ATMs may not release for several days. While my credit union has a documented policy of holding for five days, in practice, network deposits release $50 immediately, and the remainder at the end of the next business day. This is for checks in the under $1000 range — they might be fussier over larger amounts.

The incredible saturation level of Co-Op terminals has another benefit. If the potential deposit delays are not a problem for you, it may not be necessary for you to give up your credit union account when you move. If the area you are moving to has a sufficient number of terminals, you can just file an address change and continue to use your existing account. Between network terminals, web access, and phone access, it should never be necessary to visit an actual branch after your account is opened. And given that some credit unions can be joined by mail, you may never actually have to visit your credit union. This can be useful if there is nothing in your area that you qualify for, but you do qualify for some other type of affiliation at a distant credit union.

To find out if your credit union is part of the Co-Op Network, you have several options. Look at the back of your ATM card, the Co-Op logo is triangular with the word Co-Op visible. Participating credit union ATMs will have a Co-Op logo posted or will mention it on the screen. You can see if your credit union turns up on the ATM locator, or you can just call and ask. (Hey, I’m a geek — I think of technical solutions first.)

For some reason, credit unions do not highlight the Co-Op Network as much as they should, which may contribute to the continuing popular notion that credit unions do not have enough ATMs. In practice, at least in non-rural areas, ATM availability now favors credit unions over banks, once you know the secret.

So check out your area, and see if you can give the commercial banks the old heave-ho.