What's in It for a Cash Buyer?
If you planned on buying a car for cash, there might still be some value in taking out a zero-percent loan. The biggest benefit is that it allows you to keep your money free for other purposes, such as an emergency fund or for investment. There is no penalty for paying off the loan early. Having financed a car appears as a positive mark on your credit report. Buying for cash doesn't show up at all.
In some cases, the dealerships may be getting an incentive from the automaker to promote a zero-percent loan, so taking the dealer's financing may help you obtain a better price on the vehicle. The automaker typically pays the dealership a bonus on the back end of the deal, which in turn would allow it to be more flexible with the price. It isn't a common occurrence, but something you should be aware of in case it comes up.
Zero Percent Do's
Do make sure you really want the car. Just because a car has a zero-percent loan offer doesn't mean it is the right car for you. Make sure you test-drive it to be sure it fits your needs.
Do get pre-approved for a car loan. It is still a good idea to secure financing with your bank or credit union before you go car shopping. This pre-approval can serve as a backup loan in case you don't qualify for a zero-percent offer. It's also useful to have a loan in hand so you can compare its interest rate to the dealership's financing. You might decide your bank loan, and the dealership's bonus cash offer makes the most sense for you.