T-Mobile claims that it now has more customers than AT&T — at least, depending on how you count them. In its second quarter earnings report, T-Mobile announced that it now has 98.3 million total customers, saying that it has overtaken AT&T “in total branded customers across both postpaid and prepaid.” The surge in subscribers is due to T-Mobile’s acquisition of Sprint, as this is the first time that T-Mobile is counting Sprint subscribers following their blockbuster merger.

But looking a bit more closely at the numbers, T-Mobile may not be making an apples-to-apples comparison. T-Mobile uses the term “total customers” to describe its scale, and it’s comparing those to AT&T’s postpaid and prepaid “subscribers and connections,” as reported in the carrier’s Q2 2020 earnings. AT&T listed 92.9 million customers across its postpaid and prepaid categories, which is indeed lower than the 98.3 million total customers T-Mobile reported.

But if you add in AT&T’s “Reseller” category, which accounted for 6.7 million customers, AT&T then has 99.6 million customers, meaning that AT&T would remain in second place. The carriers also seem to have different ways of counting connections to things like watches, tablets, and cars. AT&T has a whole separate “Connected Devices” category with an additional 71.8 million connections.

“The numbers speak for themselves,” a T-Mobile spokesperson said in a statement sent to The Verge after the original publication of this article. The spokesperson said that T-Mobile leads in postpaid, postpaid “other” (which includes devices that aren’t phones), and prepaid categories of customers, which would mean it leads in “total customers” among those categories.

But it’s still tricky to tell which company is really in the lead. We have to rely on the carriers’ own math for these calculations, and the categories don’t necessarily match from company to company.

Update August 7th, 7:22PM ET: Added statement from a T-Mobile spokesperson.