Iowa Electronic Markets

The Iowa Electronic Markets (IEM) is the oldest continuously operating real-money prediction market in the United States. Run by the Henry B. Tippie College of Business at the University of Iowa since 1988, it is a not-for-profit academic research and teaching project, not a commercial venue. If you are coming here expecting to size a position on the next election, stop — the caps are tiny on purpose.

Overview

IEM lists contracts that pay $1 if a specified outcome occurs and $0 otherwise. Traders buy and sell these contracts against each other on a simple continuous double auction. Deposits and withdrawals are real US dollars, but the regulatory structure is built entirely around academic research, which is why the markets have strict investment caps and limited participant pools.

Market Coverage

Two broad categories run at any given time: political markets (US presidential elections — vote share and winner-take-all contracts — plus occasional congressional and state-level markets) and economic indicator markets (historically including Federal Reserve policy and corporate earnings surprises). Sports, entertainment, crypto, and weather are not offered. There are no prop-style markets.

Pricing & Fees

There are no commissions, no vig, no bid-ask spreads imposed by the house. The only cost is the natural spread between buyers and sellers on the open orderbook. This is one of the reasons IEM has produced decades of academic papers on prediction-market efficiency: there is effectively no friction tax on price discovery.

Banking

Deposits are by check or money order mailed to the University of Iowa. There is no ACH, no card, no PayPal, no crypto. Withdrawals are processed by paper check. Account minimum is $5 and the maximum lifetime investment is $500 per trader, set by the CFTC no-action letter. Yes — five hundred dollars, total, for the life of your account.

Ongoing Promos / Liquidity Programs

None. IEM does not pay for liquidity, does not run promotions, and does not advertise. It is a research instrument and a classroom tool for finance and political science courses.

Regulatory Reality

IEM operates under a pair of CFTC no-action letters: the first issued February 5, 1992 to the predecessor Iowa Political Stock Market, and CFTC No-Action Letter 93-66 dated June 18, 1993 for the broader IEM. The letters permit IEM to offer real-money event contracts without registering as a futures exchange, conditioned on the following: (1) the market is operated for research and teaching purposes by the University of Iowa, (2) there is no commercial profit motive, (3) individual investment is capped at $500, (4) no advertising to the general public, and (5) participation is primarily drawn from the academic community (political markets are capped at 2,000 traders; corporate earnings and economic indicator markets are limited to 1,000 traders drawn from participating universities). This is not a commercial license. It is an academic exemption, and the caps are the price of the exemption. The letters have been renewed and refined but never superseded. IEM remains legal, lawful, and real-money for US residents — the only prediction market where both of those have been true continuously for 30+ years.

User Experience

The IEM website at iemweb.biz.uiowa.edu looks exactly like what it is: a 1990s-era university research project that has been maintained but not redesigned. Order entry is form-based, no mobile app exists, and charts are functional rather than pretty. That said, the orderbook works, settlement is clean, and the academic transparency around data access is unmatched.

The Bottom Line

IEM is not a place to make money. It is a place to participate in the cleanest, longest-running real-money prediction-market experiment in the United States, with a $500 lifetime cap and zero fees. Finance students, political scientists, and anyone interested in the academic history of event-contract pricing should open an account. If you want size and depth, look at Kalshi, Polymarket, or FanDuel Predicts instead.