Unless you plan to pay cash, you should get preapproved for a loan from a bank or credit union.
While there's no obligation to use the preapproval, you'll at least be armed with a comparison when the dealership offers its best loan terms.
Sometimes, Jones said, people are surprised that they don't qualify for an advertised special rate. Generally speaking, the higher your credit score, the more likely you are to snag those best deals. Credit scores of 719 or higher help you qualify for the lowest rates, according to Bankrate.
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"Get preapproved ahead of time, even if just to see what kind of rate you can expect," Jones said.
The current average interest rate on a five-year (60 months) loan for a new car is just under 5 percent, according to Bankrate. However, consumers with good or excellent credit could qualify for a lower rate while those with lower scores could pay a much higher rate.