One of the keys to running a successful business is repeat business. Convincing people to come in the door is one thing; getting them to come back is something completely different. Insights firm Sense360 recently released its “customer frequency” data from the top 50 limited service chains (read: fast food) for June 2017 – and the numbers, which are determined from a minimum of at least 5,000 visits to each restaurant, are intriguing. McDonald’s was far and away the most frequented chain.

The average McDonald's customer had 2.19 visits, meaning that customers not only went to the chain, but they went back within the same month. MickeyD’s was the only brand to pass this two visit threshold. The number two chain on the list, Starbucks, had a customer frequency score of 1.97. Think about that: Customers showed more repeat business at McDonald’s than at Starbucks – a place known for doling out people’s daily coffee fixes.

As might be expected, chains that specialize in coffee did particularly well: Tim Horton’s ranked #4 and Dunkin' Donuts ranked #5 with scores of 1.82 and 1.79 respectively. Chick-fil-A, known for its loyal followers was sixth on the list. And the country’s largest chain by number of locations, Subway, was eighth.

However, the two biggest surprises to me were the chains that were third and seventh. Sonic actually had the third highest frequency score, with 1.83 visits for the month. And with 1.74 visits on average, Whataburger was the seventh best performing chain. Seeing as these two chains finished eighth and sixteenth respectively when it came to their national share of total visits, they certainly appear to be over-performing when it comes to repeat customers.

Of course, as implied above, a number of different factors play into repeat visits. Larger chains with more locations will find it easier to get customers back again. And coffee chains are probably more likely to see someone dropping in on a regular basis as opposed to, say, a taco shop. Still, looking at repeat business is an interesting look at which chains have those all-important loyal customers.

[h/t Nation’s Restaurant News]

This article was originally posted on Foodandwine.com.