(NEXSTAR) – The vast majority of riders are risking overpaying when they call an Uber or Lyft, a new research paper found.

Researchers with Harvard and Johns Hopkins’ business schools compared prices on 2,238 ride requests in New York City to find out if Uber or Lyft was cheaper.

They found recurring price gaps between the two platforms, but said “neither rideshare app is consistently more expensive than the other.” Sometimes Uber was pricier, other times it was Lyft.

The prices had a 14% gap on average, or about $3.50 on the routes they tested, Jeffrey Fossett, Michael Luca and Yejia Xu wrote in their paper.

The pattern held true for short rides and longer rides. Price also didn’t have a strong connection to wait time, meaning paying more didn’t get you a quicker ride, and saving money didn’t mean waiting longer.

Two journalists at the Washington Post conducted their own version of the experiment in San Francisco and got the same result. Sometimes Uber was cheaper and sometimes Lyft was cheaper, but they took turns being the better deal.

The lesson? The academic and journalistic researchers make the same recommendation: Check both apps.

It may sound obvious, but most people aren’t doing it, the researchers found. Only 16% of riders are checking both platforms before selecting a ride, according to the research.

That means 84% of riders are potentially spending money they don’t need to. If you have both apps downloaded and don’t have loyalty to either platform, the data suggests that most of the time you can save at least a few dollars by simply comparing prices. Not doing so is costing rideshare users in New York City alone an estimated $300 million.