PolyTerminal
What is the difference between a limit order and a market order?
Every order on Polymarket's prediction markets is, underneath, a limit order: a price and a size. The documentation states that all orders on Polymarket are limit orders, and it describes a market order as a limit order whose price lets it execute at once against resting orders. A limit order asks for this price or better, so it may wait and may never fill. A market order asks for the trade now, so it takes what the book offers.
In Polymarket's developer tools (its software development kits, or SDKs, and its API) a limit order is sized in shares, while a market order is sized by side: a market buy is sized in dollars to spend and a market sell in shares to sell. The dollar amount of a market buy is a figure before fees, so fees come on top of it. A market order never rests on the book, so whatever cannot fill at once is cancelled.
What do GTC, GTD, FOK and FAK mean?
Time in force says how long an order may live and how it must fill. Polymarket lists four values: GTC, GTD, FOK and FAK.
| Value | Stands for | If it does not fill at once |
|---|---|---|
| GTC | Good till cancelled | It stays in the book until it is filled or you withdraw it |
| GTD | Good till date | It rests until it lapses, slightly before the expiry you set |
| FOK | Fill or kill | Nothing fills unless the whole order can fill at once |
| FAK | Fill and kill | What fills at once is kept and the rest is cancelled |
In Polymarket's tools, GTC and GTD are the lifetimes of limit orders, while FOK and FAK are the two execution types of market orders, the first for traders who cannot accept a partial fill and the second for those who can.
A GTD order lapses one minute before its stated expiration, as a security margin, so a given lifetime means adding that minute to your expiry time. The expiry must also lie at least 3 minutes ahead, or the order is rejected, which makes the shortest useful lifetime about two minutes.
What is a post-only order?
A post-only order is a limit order with a guard: it is refused when it would match at once instead of resting. It makes sure you add to the book instead of taking from it, so you are the maker. On prediction markets, makers pay none in Polymarket fees, so an accepted post-only order avoids the taker fee, although a builder can still charge its own fee. The flag goes on a GTC or GTD limit order.
How does a marketable order match?
An order is marketable when a buy is priced at or above the lowest ask, or a sell at or below the highest bid; the ask is the lowest sell offer in the book and the bid is the highest buy offer. The exchange matches it against the resting orders on the other side, best price first, and the sender becomes the taker, the one who removes liquidity. An order that is not marketable rests on the book, and its owner becomes a maker, the one who adds liquidity, once someone trades against it. The limit price is a worst case, not the price you get: price improvement always benefits the taker.
An order can fill in pieces. What happens to the unfilled rest depends on the type, as the table above shows: a limit order keeps it alive for as long as its time in force allows, a FAK order cancels it, and a FOK order refuses the whole trade.
Can you cancel or change an order?
Through the API an order can be cancelled up to the moment it matches, except while a marketable order sits in a pending delay window. Cancelling reaches only what is still open: only the unfilled part of an order can be cancelled. At the exchange level an order cannot be edited in place, so changing a price or a size means cancelling it and placing a new one. Orders also end without you: a GTD order lapses at its expiry, and in sports markets resting limit orders are automatically cancelled once the game begins, at the official start time, but if a game starts earlier than scheduled, orders may not be cleared in time.
What happens between pressing buy and settlement?
An order starts as a signed message on your side, is paired with a counterparty by Polymarket's operator, and reaches the blockchain only once it has been matched. In three stages:
- On your side. An order says which outcome token you want, whether you buy or sell, at what price, for how many shares and until when, plus a timestamp that keeps it unique. Orders are EIP-712 signed messages (a standard way of signing structured data), and your signature authorizes the settlement contract to carry out that one trade.
- At the exchange. The operator checks who signed, whether your balance and allowances cover the order, and whether the price fits the market's tick, with size limited by your available balance minus what open orders already reserve. A marketable order is then matched, and any other order waits on the book.
- On the chain. The operator sends the matched trade to the blockchain, where settlement is atomic, so the whole trade succeeds or nothing happens. After finality on Polygon, what you hold has changed and the trade is listed among your past trades.
A new order gets a status: live means it rests on the book, matched means it matched at once, and delayed means a marketable order was accepted into a delay window. A fourth status, unmatched, appears in the Order Lifecycle table and in the Place Orders API example, and the pages word it differently: as a marketable order placed on the book after the delay ended without a match on one and as a marketable order that failed to delay, although placing it still succeeded on the other. This guide therefore does not define it. After a match the trade moves from MATCHED through MINED to CONFIRMED, which is final, with RETRYING and FAILED for transactions that go wrong.
What is the taker delay?
Some markets hold a marketable order for a moment before matching it. The Order Lifecycle page says this taker delay is used on selected crypto and finance up/down markets and lasts 250 ms, and Polymarket's API reference for market info gives 250 ms too. The Predictions changelog records two later changes for crypto markets:
| Date | Crypto taker delay |
|---|---|
| Aug 17, 2026 | 50 ms, down from 250 ms |
| Sep 4, 2026 | 150 ms, up from 50 ms |
Changes to the crypto taker delay in the Predictions changelog. Source: docs.polymarket.com/changelog/predictions, checked .
250 ms is the figure the changelog lists as the delay before its Aug 17, 2026 entry, so those two pages look older than the changelog, and this guide treats the newest entry as current for crypto markets: 150 ms. The changelog covers only crypto markets, so the delay on finance up/down markets is not documented there. While an order is held, it is pending and cannot be cancelled. Perps has a taker delay of its own, 20 ms for orders that match immediately on entry, according to the Perps changelog. The crypto Up/Down guide explains what the delay means for short windows.
Why can an order be rejected?
A market can refuse an order for a price off its tick grid (see the tick section of the order book guide), a size under its minimum (orders smaller than the minimum order size are rejected), a post-only order that would match at once, or a GTD expiry that is too close.
What is builder attribution?
On prediction markets, an app that routes orders to Polymarket can attach its builder code to them. The code is a 32-byte hexadecimal string that identifies the builder's profile, and it is part of the signed order, so it is set before signing. A matched order is credited to the builder's profile, and orders that never matched are absent from the builder's trade results. Builders can also charge a fee within limits that Polymarket enforces: at most 1% on taker orders and 0.5% on maker orders. Such fees are additive: they stack on top of platform fees and never replace them. Orders placed through PolyTerminal carry PolyTerminal's builder code, and PolyTerminal may charge a builder fee on top of Polymarket's own fees. The fees guide has the details.
What does the PolyTerminal Predict order form offer?
Which of Polymarket's options an interface offers is that interface's choice.
How are Perps orders different?
Perps are a separate product with their own order rules and fees. There, time in force takes the values GTC, IOC and FOK (IOC means immediate-or-cancel), a post-only order is rejected if it would take liquidity, and a reduce-only order cannot increase exposure. On Perps the fee tier follows an account's trailing 30-day trading volume, so the rule that makers pay nothing does not carry over. The Perps guide explains the rest.
FAQ
Does Polymarket have market orders?
In effect, yes. Every order is a limit order, and a market order is a limit order whose price lets it execute at once against resting orders. In Polymarket's tools a market order is either FAK, which keeps a partial fill and cancels the rest, or FOK, which fills in full or not at all.
What is the difference between FOK and FAK?
Both must fill immediately. A FOK order fills in full or not at all, so it either completes or leaves nothing behind. A FAK order fills whatever the book offers at your price and cancels the unfilled remainder, so a partial fill is possible.
Can I cancel a partly filled order?
You can cancel the part that has not filled, but not the part that has. Polymarket's documentation says only the unfilled part of an order can be cancelled. A marketable order held in a delay window cannot be cancelled until the delay ends.
How long does a GTD order last?
Until the expiry you set, less a margin: Polymarket expires a GTD order one minute before its stated expiration, and the expiry must lie at least 3 minutes ahead when you place it. The shortest effective lifetime is therefore about two minutes.
Sources and checks
Every rule quoted in this article comes from the registry below. Each row names the official page and the day it was compared with the text.
All 44 rules used in this article
| Rule | Value | Official source | Checked |
|---|---|---|---|
| What every order is | all orders on Polymarket are limit orders | docs.polymarket.com/ | |
| What a market order is | a limit order whose price lets it execute at once against resting orders | docs.polymarket.com/ | |
| How market orders are sized in Polymarket's SDKs and API | a market buy is sized in dollars to spend and a market sell in shares to sell | docs.polymarket.com/ | |
| Dollar amount of a market buy | a figure before fees | docs.polymarket.com/ | |
| A market order and the order book | never rests on the book, so whatever cannot fill at once is cancelled | docs.polymarket.com/ | |
| Order types (time in force) on the Order Lifecycle page | GTC, GTD, FOK and FAK | docs.polymarket.com/ | |
| When a GTD order really expires | one minute before its stated expiration | docs.polymarket.com/ | |
| Smallest distance between now and a GTD expiration | 3 minutes | docs.polymarket.com/ | |
| Shortest effective lifetime of a GTD order | about two minutes | docs.polymarket.com/ | |
| Post-only order | is refused when it would match at once instead of resting | docs.polymarket.com/ | |
| Fees on makers | none | docs.polymarket.com/ | |
| Order types a post-only flag goes with | a GTC or GTD limit order | docs.polymarket.com/ | |
| When an order is marketable | a buy is priced at or above the lowest ask, or a sell at or below the highest bid | docs.polymarket.com/ | |
| Who gets price improvement | price improvement always benefits the taker | docs.polymarket.com/ | |
| When an order cannot be cancelled | except while a marketable order sits in a pending delay window | docs.polymarket.com/ | |
| Cancelling a partly filled order | only the unfilled part of an order can be cancelled | docs.polymarket.com/ | |
| Editing an order | cannot be edited in place | docs.polymarket.com/ | |
| Resting orders in sports markets | automatically cancelled once the game begins | docs.polymarket.com/ | |
| Caveat on the automatic cancelling of sports orders | if a game starts earlier than scheduled, orders may not be cleared in time | docs.polymarket.com/ | |
| How an order is authorized | EIP-712 signed messages | docs.polymarket.com/ | |
| What limits the size of a new order | your available balance minus what open orders already reserve | docs.polymarket.com/ | |
| Settlement of a matched trade | atomic, so the whole trade succeeds or nothing happens | docs.polymarket.com/ | |
| The unmatched status as worded on the Order Lifecycle page | a marketable order placed on the book after the delay ended without a match | docs.polymarket.com/ | |
| The unmatched status as worded in the Place Orders API example | a marketable order that failed to delay, although placing it still succeeded | docs.polymarket.com/ | |
| Markets with a taker delay (Order Lifecycle page) | selected crypto and finance up/down markets | docs.polymarket.com/ | |
| Taker delay printed on the Order Lifecycle page | 250 ms | docs.polymarket.com/ | |
| Taker delay printed on the Get CLOB market info reference | 250 ms | docs.polymarket.com/ | |
| Crypto taker delay in the newest changelog entry (Sep 4, 2026) | 150 ms | docs.polymarket.com/ | |
| An order inside a delay window | it is pending and cannot be cancelled | docs.polymarket.com/ | |
| Perps taker delay (Perps changelog, Jun 10, 2026) | 20 ms | docs.polymarket.com/ | |
| Orders below the minimum size | orders smaller than the minimum order size are rejected | docs.polymarket.com/ | |
| Minimum order size as described on the Place Orders page | the minimum number of shares accepted for an order | docs.polymarket.com/ | |
| Minimum order size as described on the Market Details page | an amount in USDC | docs.polymarket.com/ | |
| What a builder code is | a 32-byte hexadecimal string that identifies the builder's profile | docs.polymarket.com/ | |
| Where the builder code sits in an order | part of the signed order | docs.polymarket.com/ | |
| Unmatched orders in builder trade results | orders that never matched are absent from the builder's trade results | docs.polymarket.com/ | |
| Highest builder fee on taker orders (prediction markets) | 1% | docs.polymarket.com/ | |
| Highest builder fee on maker orders (prediction markets) | 0.5% | docs.polymarket.com/ | |
| How builder fees combine with platform fees | they stack on top of platform fees and never replace them | docs.polymarket.com/ | |
| Time-in-force values | GTC, IOC and FOK | docs.polymarket.com/ | |
| Post-only | is rejected if it would take liquidity | docs.polymarket.com/ | |
| Reduce-only | cannot increase exposure | docs.polymarket.com/ | |
| What sets the Perps fee tier | trailing 30-day trading volume | docs.polymarket.com/ | |
| Changes to the crypto taker delay in the Predictions changelog | Changes to the crypto taker delay in the Predictions changelog | docs.polymarket.com/ |
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PolyTerminal is an independent interface for Polymarket and is not operated or endorsed by Polymarket. Orders placed through PolyTerminal carry PolyTerminal’s Polymarket builder code, and PolyTerminal may charge a builder fee on top of Polymarket’s own fees. This page is educational and is not investment advice. Rules were compared with the official documentation on Oct 19, 2026; check the source before you act on a number.