The total was close to beating January's record $385.2m in wagers, while the revenue total was up from $12.7m in February, increasing due to the March Madness basketball tournament.
Basketball handle for March was $205m, accounting for 53% of all sports betting wagers for the month.
The NFL season concluded in February, and the new MLB regular season started on 20 March.
Total sports wagering gross revenue for 2019 so far amounts to $63.1m.
Elsewhere, casino win for March was $223.2m, increasing 16% year-on-year, while internet gaming win was $39.1m, rising 53%.
The state's total gaming revenue grew 35% year-on-year to $294m.
