Revenue also rose to $8.1m, up 22% month-on-month.
On an annual basis, Pennsylvania handle almost trebled, posting $59.3m for July 2019, with revenue up from $2.9m too.
The Keystone State's 12 casinos have all reopened following closures during the coronavirus pandemic, although 94% of all wagers were placed online.
FanDuel generated the highest handle ($70m), whereas DraftKings registered the highest revenue ($1.9m).
UFC 251 was the most bet-on UFC event in BetRivers/Play SugarHouse history and, during MLB's opening weekend, BetRivers, Play SugarHouse and FanDuel all recorded historic highs.
However, comparisons to New Jersey show Pennsylvania is lagging behind, as the Garden State generated $315.1m in handle for July.
