Best Betting Platforms for NFL Arbitrage in 2026: Fees, Coverage and the Key-Number Problem

The quick answer

Cheapest NFL leg before kickoff: Novig. No fee for maker or taker on pre-game straight trades.

Visible depth: Kalshi. Its public order books show spread and size before you trade.

Best if you post rather than take: Polymarket US. Makers collect a rebate.

Closest settlement match to a sportsbook: ProphetX. It lists whole-number spreads and voids them on a push, the way a book refunds one.

Limited footprint: DraftKings Predictions. It's available in a limited set of states, and its NFL menu varies, so check the app for yours.

What breaks NFL arbs: a book's whole-number line can push on 3 or 7 while every prediction-market spread sits on a half point, a tie is refunded at a book but paid at 50c on Novig, Kalshi and Polymarket US, and an inactive player's prop is refunded at a book but settled at a fair price on Novig and Kalshi.

On a $200 pre-game position with a $5.00 edge, Novig keeps the whole edge, where a Kalshi or Polymarket US taker pays about $3.60 of it. In football the larger risk is a book's -3 paired with the wrong half-point contract, which turns a 3-point result into a $102.50 loss on prices that would otherwise have paid $102.50 extra.

What NFL arbitrage is

You back both sides of an NFL market on two venues at prices that together return more than they cost, whoever wins. In the US that usually pairs a sportsbook with a prediction market, which price the same game independently.

Edges are small, so the result depends on two things: the fee on the prediction-market leg, and whether both venues settle the game on the same facts.

How we checked

This covers venues a US bettor can open and get an NFL position filled on. Fees and settlement rules come from each platform's own schedule, contract terms or house rules. Depth comes from Kalshi's public market data.

Kalshi's fee comes from its fee schedule effective 7 July 2026, checked 7 October. DraftKings Predictions' fee comes from DraftKings' own fee disclosure. The push and tie figures come from the nflverse games file, covering the 2015 through 2025 seasons. Everything else was checked again on 7 October.

The platforms, ranked for NFL arbitrage

We ranked on what the prediction-market leg costs before kickoff. On depth alone, Kalshi would rank first.

1. Novig: the cheapest pre-game leg

Novig charges neither side on a pre-game straight trade. In-game, takers pay 0.03 x price x (1 - price) per contract, or 75c per 100 contracts at even money, and the maker fee is $0 on every trade type.

Novig runs on Ludlow Exchange, LLC, a CFTC Designated Contract Market. Its NFL Winner and Prop contracts were certified on 23 July 2026 and its Spread and Total contracts on 24 July.

Its NFL contracts date from late July 2026 and we found no public depth data for them, so test a fill at your size first.

Best for: the prediction-market leg of a pre-game arb on sides, totals and props.

2. Kalshi: depth you can check

Kalshi lists NFL game winners, spreads, totals and player props, and its order books are public. Games in the coming week tended to show tighter spreads and more size than games further out, with prime-time games drawing the deepest books.

Its standard taker fee is $1.75 per 100 contracts at 50c. Kalshi's NFL game, spread and total series also charge the resting side, so posting there isn't free either.

Best for: filling size in the days before kickoff.

3. Polymarket US: paid to post

Polymarket US lists NFL games. Its taker coefficient rose to 0.0695 on 1 October 2026, which is $1.74 per 100 contracts at 50c, and makers are paid $0.31 per 100 at the same price. Polymarket US changed some fees again on 7 October 2026, so check its current schedule before relying on these figures.

Best for: the resting side of an arb.

4. ProphetX: settles a push like a book

ProphetX takes 2% of net gains per market on straight trades, so a position held to settlement pays only on the winning leg. Its football rules allow whole-number spreads and totals and void them, returning collateral, when the result lands exactly on the number. A tied game voids its moneyline the same way. Of the prediction markets whose rules we read, only ProphetX offers a +3 that settles identically to a book's -3.

Best for: whole-number spreads paired with a sportsbook.

5. DraftKings Predictions: limited states

DraftKings Predictions is available in a limited set of states, and its NFL menu can differ from the other venues here, so check the app for what it lists where you are. DraftKings' own fee disclosure charges $0.02 per contract each time you open or close a position priced from 30c to 94c.

Best for: bettors where it's available who already hold a DraftKings login.

The sportsbook leg

A sportsbook such as FanDuel, DraftKings or BetMGM usually supplies the other leg, with the vig already in its price. DraftKings' house rules include overtime in every football bet and count it in second-half and fourth-quarter markets.

What an NFL arb keeps after fees

A pre-game arb on one game: a sportsbook leg at decimal 2.10 (+110) and a prediction-market leg at 50c. Stake $97.50 at the book and buy 205 contracts for $102.50. Total outlay is $200.00. The book leg pays $204.75 and the contracts pay $205.00, so profit before fees is $4.75 or $5.00.

Where NFL arbs break

The key-number problem

Sportsbooks often hang whole-number spreads such as -3, and DraftKings' rules settle a bet that lands exactly on the number as a push, stake returned. Novig, Kalshi and Polymarket US use half-point spreads only, so their contracts can't push and always resolve yes or no.

Across the 2015 through 2025 seasons, 449 of 3,028 games (14.8%) ended with a 3-point margin and 263 (8.7%) with a 7-point margin, the two most common results. Of the 433 games that closed at exactly 3, 44 (10.2%) landed on it, against 11 of the 172 that closed at 7 (6.4%).

Say the book has Team A -3 and you hedge with a prediction-market contract that Team A does not win by more than a half-point number, using the $200 position above. Team A wins by exactly 3:

Paired with "no" on A by more than 3.5: the book refunds $97.50 and the contract pays $205.00. You collect $302.50, a $102.50 gain on top of the arb.

Paired with "no" on A by more than 2.5: the book refunds $97.50 and the contract loses. You collect $97.50, a $102.50 loss.

A scanner shows both as the same arb, though only the first pairing holds on a 3-point result.

Ties

There were 10 ties in those 3,028 games. When one happens, DraftKings settles a two-way moneyline as a push and ProphetX voids its moneyline. Novig, Kalshi and Polymarket US instead pay 50c per contract to each side.

On the example above, bought at 50c, the 205 contracts return $102.50 and the book refunds $97.50, so you're back to $200.00. A leg bought at 60c would lose 10c a contract.

Player props and inactives

DraftKings voids a prop on a player who doesn't play a snap, and ProphetX requires a snap for a prop to stand. Novig settles that player's contract to Void and pays it at a fair value taken from the 30 minutes of trading before the news, while Kalshi resolves an active player who never plays to a last fair price of its choosing.

A book-against-Novig prop arb on an inactive player therefore refunds one leg and marks the other to market. In Novig's own example, a YES bought at 52c settled at 45c.

Thursday, Sunday and Monday timing

On Kalshi, depth builds as kickoff gets closer. Novig's no-fee window closes at kickoff, so a fee-free Thursday arb on Novig has to be in place before the 8:15 p.m. kickoff.

What to look for

Fee on the prediction-market leg: a taker fee near $3.60 takes most of a $5.00 edge on $200, and a leg with no pre-game fee keeps all of it.

Line type: pair a book's whole number with the half-point line that wins on the push, or use ProphetX's matching whole number.

Tie rules: price the 50c tie payout into any moneyline leg bought well above 50c.

Prop rules: pair a book with ProphetX for props, or accept fair-value settlement on Novig or Kalshi.

Your state: sports contracts are restricted or litigated in several states, and the list changes with court rulings.

NFL arbitrage FAQ

What is the best app for NFL arbitrage?

For a pre-game leg, Novig, which charges neither side on a pre-game straight trade. For depth you can check before kickoff, Kalshi. For a whole-number spread that pushes like a book's, ProphetX, the only prediction market whose rules we read that lists one.

Does overtime count in NFL bets?

Yes for full-game markets at every venue whose rules we read. DraftKings and Novig also count overtime in second-half markets.

Sources

All checked 7 October 2026 except where noted.

Novig fee schedule: support.novig.com/en/articles/16195057-fees-on-novig

Novig Fair Value Settlement: support.novig.com/en/articles/16163706-what-is-fair-value-settlement-fvs

Novig NFL contract certifications and terms: ludlowexchange.com/filings (NFL Winner and Prop certified 23 July 2026; Spread and Total 24 July 2026)

Kalshi NFL series fee types: Kalshi public API (KXNFLGAME, KXNFLSPREAD, KXNFLTOTAL); Kalshi FOOTBALLGAMEWIN and FOOTBALLENTITYSTAT contract terms

Kalshi fee schedule: kalshi.com/docs/kalshi-fee-schedule.pdf (effective 7 July 2026)

Polymarket US fee schedule and sports FAQ: docs.polymarket.us/fees (effective 1 October 2026); docs.polymarket.us/faqs/sports-faqs

ProphetX Football Rules and Understanding Fees: ProphetX help center, updated 6 October and 19 August 2026

DraftKings Predictions fee disclosure: myaccount.draftkings.com/documents/fee-disclosure?product=predict (Predictions standard pricing)

DraftKings Sportsbook house rules, general and football sections: Massachusetts Gaming Commission filing, implementation date 26 August 2025

NFL margins, closing spreads and ties, 2015 to 2025: nflverse games data, github.com/nflverse/nfldata