Kalshi Turns 4

This is an update in a series of posts looking at Kalshi trading volume on its July 1st anniversary

You can also read previous posts for its one-year and two-year and three-year birthdays.

One caveat to everything below is that we’re missing market data from 10 days: 2024-10-13, 2024-11-15, 2024-12-10, 2024-12-13, 2025-01-01, 2025-01-04, 2025-01-06, 2025-02-13, 2025-04-01, 2025-05-09.

Top events

In 2023, we defined “top” events as over $500,000.  In 2024, the threshold was upped to $1M because there were 60 events over $500,000.  This year, $1M isn’t practical because there are 558 Kalshi events with volume over $1M (and 866 markets over $500K) out of 3,740 total events.

So here are the 13 event contracts with over $20 million in trading volume over the past year:

Event TickerVolumeEvent details
PRES-2024-KH272,667,844Harris wins presidential election
PRES-2024-DJT261,464,867Trump wins presidential election
KXNBA-25-IND57,978,220Indiana Pacers 2025 NBA champs
POPVOTE-24-D42,828,274Democrat wins POTUS popular vote
KXNBA-25-OKC35,536,872Oklahoma City 2025 NBA champs
POPVOTE-24-R32,111,546Republican wins POTUS popular vote
POPVOTEMOV-24-R-B-2.523,284,043Popular vote margin of victory 2-2.99%
KXMARMAD-25-FL23,268,398Florida wins March Madness
POPVOTEMOV-24-R-B-3.523,212,020Popular vote margin of victory 3-3.99%
SENATEAZ-24-R22,406,350GOP wins 2024 Arizona Senate race
KXMASTERS-25-RM22,031,002Rory McIlroy wins Masters
POPVOTEMOVSMALL-24-R-B1.420,429,081Popular vote margin of victory (0.25% ranges)
KXNBAGAME-25JUN16INDOKC-IND20,169,693NBA 2025 Championship Game 5

Eight were election-related (seven for the 2024 US presidential election and one for the Arizona Senate race) despite Kalshi winning their court case extremely late in the election cycle. After launching and then halting markets on September 12th, Kalshi was finally given the green light to offer election contracts by the DC Circuit Court on October 2nd, barely one month before Election Day.

Five of the remaining thirteen were sporting event championships, if we include the Masters Golf Tournament:

  • Indiana Pacers 2025 NBA champs
  • Florida wins March Madness
  • Rory McIlroy wins Masters
  • Oklahoma City 2025 NBA champs
  • NBA 2025 Championship Game 5

Kalshi volume over time

PeriodVolume
Year One (21-22)38,749,075
Year Two (22-23)119,700,082
Year Three (23-24)270,730,577
Year Four (24-25)4,552,902,722
Total4,982,082,456

Elections & sport markets grew the pie

Without getting into a discussion about their legal status, both election and sport event contracts seem to have increased trading in other categories of markets:

Category21-2222-2323-2424-25Total
Sports                          0                           0                               0     1,864,635,946   1,864,635,946
Politics      4,868,164      6,253,340         5,261,622   1,702,297,978   1,718,681,104
Financials   11,264,537   83,037,437   209,721,172        131,899,008        435,922,154
Crypto                          0                            0           4,565,007        325,666,411        330,231,418
Economics      6,225,457   19,916,845      30,059,010        187,102,237        243,303,549
Climate and Weather      6,513,485      8,416,173      10,154,412        167,461,886        192,545,956
Entertainment      1,382,846          388,063         7,569,453        118,864,687        128,205,049
Science and Technology          688,727          334,671         1,227,284           15,863,121           18,113,803
World      1,547,242          113,222             160,561           13,026,870           14,847,895
Companies                          0               10,815         1,602,503           11,006,949           12,620,267
Elections                          0                            0                              0            12,340,287           12,340,287
Health      5,760,521          954,945             238,414              1,832,257              8,786,137
Transportation          498,091          274,571             171,139                  299,447              1,243,248
Social000                  392,330                  392,330
Mentions000                  206,389                  206,389
Education000                        6,919                        6,919

Economics, Climate and Weather, Entertainment, Science and Technology, World, Companies, and Health categories all saw massive increases in volume over the past year compared to the previous few years.

Data Sources

Kalshi Market Data and Trade Data are publicly available in their “Regulatory” section.

Kalshi API documentation: https://kalshi.com/api

Here is Kalshi contract data over time broken down by category.

Again, there were 10 days missing from the 2024-2025 data listed above. The Kalshi API did not provide all categories, and assumptions were made about categories based on other contracts, as well as any contract on Kalshi Klear having the same category as the corresponding market on LedgerX. (i.e.,  KXCPI = CPI)

For Kalshi market calibration, check out the calibration.city website. For accuracy, see brier.fyi.