"We expect to see high volume across most legal U.S. markets in March, but Indiana's circumstances were unique with March Madness played entirely in Indiana," said Jessica Welman, lead analyst at PlayIndiana. "It's hard to know just how much it moved the needle, but March's results were clearly fueled by a huge volume of NCAA Tournament games all in one place and by a number of fans who traveled to Indiana and then bet legally as they attended games. We may never see a betting event quite like that ever again."

Indiana sportsbooks brought in $316.7 million in wagers in March, according to official reporting released Monday. That is the second-most for a month in Indiana and up 15.6% from $273.9 million in February. Only January's record of $348.2 million topped March's results, pushing Indiana's lifetime handle to $3.1 billion since launch.

Sportsbooks generated $26.4 million in revenue, a 55.4% increase from $17 million in February, and only topped by the record $29.3 million set in January. March's revenue yielded $2.5 million in state taxes.

Year-over-year, March's handle was up 323.3% from $74.8 million in March 2020, a month marred by the pandemic-related shutdown of major U.S. sports.

"What a difference a year makes, even if comparing this year to last year is apples and oranges," said Nicole Russo, analyst for PlayIndiana. "Beyond the shutdowns, so much has changed in Indiana's landscape. Yet, the state continues to fare well in large part because its regulatory framework has been fair and unlike its neighbors in Illinois, consistent. That has created a resilient state industry able to withstand increased competition from neighboring states and a brutal pandemic."

Online betting accounted for 88.1%, or $279.2 million, of the state's handle, a modest decrease from 88.4% in February. $160.6 million of March's bets were on basketball, a dramatic increase from $127.2 million in February as March Madness gripped the attention of bettors.

"For a basketball-crazy state like Indiana, a dearth of local teams could have really lowered the state's handle," Welman said. "But it appears that the proximity of the tournament made up for a lack of Indiana representation."

DraftKings/Ameristar Casino led the state's operators with $111.2 million in online bets, up from $107.4 million in February and accounting for 39.8% of the state's online handle. The month produced $8.5 million in receipts, up from $3.7 million in January. FanDuel/Blue Chip Casino was second with $92.4 million in bets, up from $70.9 million in February.

$37.5 million in bets were placed at retail sportsbooks In March, up from $32.9 million in February. Hollywood Lawrenceburg led the retail market with $10.8 million in wagers.

Operators in Indiana may also receive a boost from Illinois, where Gov. J.B. Pritzker reinstated in-person registration for that state's online sportsbooks. That decision could make traveling across the border from the Chicago area more appealing.

"Indiana has always been a market that has capitalized on large markets just across its borders," Russo said. "Illinois' decision could modestly move the needle, especially for the Chicago-area casinos that have always counted on out-of-state bettors as a significant portion of their customer base."