How to Set an Order Size on Polymarket (US 2026)

How We Verify

Checked Aug 8, 2026

We checked Polymarket US’s published Glossary (Contract: you trade contracts in quantities; Size: number of contracts available to buy or sell at a given price; Order; Bid; Ask; Liquidity; Buying power; Open order), Place a Trade and Order Placement (Yes or No, a dollar amount or Max, review, swipe — no reprinted Size / Shares / Contracts / Qty field on the swipe we checked), Fractional Contracts (US fills whole event contracts only; a dollar amount buys as many whole contracts as it can; leftover returns to cash), Why does my position look down right after I buy? (same leftover-cash rule), Orders & Trading (a limit is a price you set; buying power falls when you buy contracts), Order Types (available size fills; leftover can rest), Price Impact (order size versus posted size at each price), Liquidity (posted size on the book; on the take-now walk you cannot set a custom limit price), Prices & Market Data, Spreads, Monitor Your Positions, Check Your Balance, Website vs App, What is Polymarket US, Official Orders API Overview (developer quantity — number of contracts — not a retail chip), Modify Order (price, quantity), and the official US docs index (llms.txt). We reprint only labels those pages print. If a Size / Shares / Contracts / Qty box is not on those retail pages, we describe the action instead of inventing a header. We do not reprint a live bid, ask, clip size, or personal fill. Last checked August 2026.

Reviewed by: Scott, Editor
Terms checked against: Operator-published terms, August 8, 2026
Hands-on testing: In progress — updates to follow

Who this guide is for

US adults who are about to place a new Polymarket US order and need to set the order size — how many shares, or how much dollar size, that one clip will try to buy or sell. This is not how to set a limit price, not how to read a partial fill, not how to read your portfolio, not how to tell cash from buying power, not how to cancel an open order, and not how to sell a filled position. Those pages are the cents you will pay or sell at, the middle state, the live list, withdrawable versus spendable cash, the unfilled undo, and the exit on shares you still hold. This page is typing the clip. Then we link out. Polymarket is the only live outbound on this page.

What an order size is

Official Place a Trade is the published retail input: a dollar amount, or Max. Official Glossary calls the thing you trade a contract in quantities. Official Orders & Trading is the other number — you set a price. See prediction markets vs sportsbooks if you wanted a parked sportsbook stake. There isn’t one.

How many contracts — or how many dollars — this one order asks for

Official Place a Trade + Glossary

Official Place a Trade and Official Order Placement: enter the dollar amount you want to trade, or tap Max to use your available balance. Official Glossary: a contract is what you trade in quantities — buying 100 contracts is the published teaching line, not tonight’s board — and each contract settles at $1.00 if that outcome occurs or $0.00 if it does not. The action on this page is typing that clip: how much size this order will try to buy or sell. We do not reprint a live dollar or a live lot count.

Not the limit price — that number is what you will pay, or sell at

Official Orders & Trading

Official Orders & Trading: a limit order is you set a price; the order sits until someone trades against it or you cancel. Official Glossary: an order is a request to buy or sell contracts at a chosen price. Size is the clip. Price is the cents. Mixing them up is how a $0.40 ticket becomes a 40-contract order, or the other way around. How to set a limit price is that other box. This page does not clone it.

A dollar you type is not always the contracts you keep

Official Fractional Contracts

Official Fractional Contracts: Polymarket US does not support fractional contracts. When you buy using a dollar amount, the system purchases as many whole contracts as that amount can buy at the current market price; leftover that cannot buy a full contract returns to cash. Official “Why does my position look down right after I buy?” is the same leftover-cash rule. Official teaching example uses $100 at a $0.65 Yes — that is a docs book, not tonight’s NFL board. We will not paste a live conversion onto this page.

Official dollar amount or Max · not the limit price · whole contracts only

Where the size field lives

Hard rule: if official US help names a field, we name it. If a box is not on those pages, we describe the action. Official Website vs App splits the international site from the US desk.

On the new-order card — if public US help or the live card shows it

Action, not an invented header

Official Place a Trade and Official Order Placement reprint Yes or No, a dollar amount or Max, review, then swipe to confirm. Those pages do not reprint a retail field labelled Size, Shares, Contracts, Quantity, or Qty on the swipe we checked. We will not invent one. The published retail input is a dollar amount, or Max. If the live US card already shows Size, Shares, Contracts, Amount, Quantity, or Qty, use that live word. If it only lets you type or step a number with no header, type how much you want this order to buy or sell before you confirm.

US app — not polymarket.com

Official Website vs App

Official Website vs App: US residents deposit and trade in the Polymarket US app, not on the international website. Official What is Polymarket US? is the CFTC-regulated designated contract market this record belongs to. Official Place a Trade is written for that US swipe. If a control is labelled differently in-app, follow the live screen. If the sports desk is hidden where you live, stop.

API “quantity” is not a retail Size chip we will paste on the swipe

Official Orders API Overview

Official Orders API Overview names a developer quantity field — number of contracts — and Official Modify Order names changing price and quantity. That is useful if you already have the authenticated access those pages describe. It is not permission to tell a US retail reader to open a developer portal, paste a key, or treat quantity as a phone label. Official Fractional Contracts still says the retail desk fills whole event contracts only. We describe the action on the live card instead of inventing that chip.

No invented Size tab · type the clip if the live card shows it · US app, not polymarket.com

Size is not the limit price

Official Fractional Contracts is the dollars-to-whole-contracts rule. Official Price Impact is what happens when your clip is larger than posted size. Official Liquidity is the book those other clips sit on. We name those clocks. We do not reprint a live dollar.

Size you type is your clip — Size on the book is someone else’s depth

Official Glossary + Liquidity

Official Glossary: Size is the number of contracts available to buy or sell at a given price. Official Liquidity: that posted size is resting orders other users left, waiting to be matched. Your typed amount is how much you are asking for. Their posted size is how much is sitting there. Official Price Impact: if your clip is larger than the size posted at the best price, leftover fills at the next levels and the average can move. How to read liquidity and how to read a partial fill name those clocks. We do not clone them, and we do not reprint a live book.

A dollar amount and a contract count are two ways to name the same clip

Official Place a Trade + Fractional Contracts

Official Place a Trade reprints the dollar-amount walk. Official Glossary reprints trading contracts in quantities. Official Liquidity teaching copy converts a dollar clip into shares at a docs cents print — that is help-center math, not a live NFL board. If the live card lets you type dollars, you are still buying whole contracts; leftover cash returns. If the live card lets you type contracts or shares, you are still not typing the limit price. Follow the live unit. Do not invent a toggle those retail pages do not print.

Max is available balance — not a price, and not a sportsbook stake

Official Place a Trade + Check Your Balance

Official Place a Trade: Max uses your available balance. Official Check Your Balance and Official Glossary: cash is funds not tied to open positions; buying power is cash available to open new positions after margin. How to tell cash from buying power is that split. This page only names Max as “use what the desk says you can still put on a new order.” It is not a house line and not a contest lock. We do not reprint a live available figure.

Official your clip vs posted depth · dollars vs whole contracts · Max is available balance

How to type the order size on a new order

Step 1

Open one market on the US app and confirm it still accepts orders

Official Place a Trade: from the home screen, tap any market to open it, then choose Yes or No. Official Prices & Market Data: Open accepts orders; Pre-open, Suspended, Halted, or Expired does not trade the same way. Official Website vs App: US residents use the Polymarket US app, not polymarket.com. If the sports desk is hidden where you live, stop. This page assumes you are about to type how much size this new order will ask for — not set the limit price, not cancel leftover size, and not sell a ticket you already hold.
Step 2

Find the live amount box if public help or the card shows it — then type the clip

Official Place a Trade and Official Order Placement reprint a dollar amount or Max. They do not reprint a retail field labelled Size, Shares, Contracts, Quantity, or Qty on the swipe we checked. Official Glossary already names the action: you trade contracts in quantities. If the live US card shows Size, Shares, Contracts, Amount, Quantity, or Qty, use that live word and type how much you want this order to buy or sell. If there is no header, type or step the number before you review. We do not reprint a live lot, and we will not paste an API quantity onto the phone.
Step 3

Do not type the limit price into that box — price is the other number

Official Orders & Trading: a limit is a price you set. Official Place a Trade’s printed input on the swipe we checked is a dollar amount, not a cents field. If the live card also shows Limit, Limit price, Price, or a cents box, that is How to set a limit price — leave it alone on this walk. Size is how many. Price is what you will pay or sell at. Confirm you did not swap them before you review.
Step 4

Read whole-contract leftover, then review before you confirm

Official Fractional Contracts: a dollar amount buys as many whole contracts as it can; unused cash that cannot buy a full contract returns immediately. Official Order Types: available size fills; leftover can rest as an open order. Official Price Impact: a clip larger than posted size at the best price can walk the book. Official Place a Trade: review your order details, then swipe up to confirm. Official Orders & Trading: buying power falls when you buy contracts. Cancel, selling a filled position, and the partial-fill stamp live on later how-tos. This step only checks the clip you typed.
Step 5

Stop — Portfolio, cash vs buying power, a partial fill, and a sale are later how-tos

Official Place a Trade: open the Portfolio tab to track the position. That live list is How to read your portfolio. Official Check Your Balance is cash versus what you can still put on a new ticket — How to tell cash from buying power. Official Order Types: some matched, rest still open — How to read a partial fill. Canceling leftover size and selling a ticket you already hold are their own click paths. Event contracts can settle at zero. Trade only what you can afford to lose. Nothing here is investment advice.

This is not the limit price, Portfolio, or a sale

Official Orders & Trading: you set a price on a limit. That cents box lives on How to set a limit price on Polymarket. Official Place a Trade: open Portfolio to track the position. That live list lives on How to read your portfolio on Polymarket. Official Check Your Balance is cash versus buying power. That split lives on How to tell cash from buying power on Polymarket. Official Order Types: some matched, rest still open. That split is How to read a partial fill on Polymarket. This page will not invent a US Size chip, and it will not reprint a live lot count.

The broader rest / cancel / partial walk is How to place a limit order on Polymarket. Pulling leftover size is How to cancel an open order on Polymarket. The exit on shares you still own is How to sell a filled position on Polymarket. We do not clone those pages.

API “quantity” is not a retail Size chip

Official Orders API Overview names a developer quantity field — number of contracts — and Official Modify Order names changing price and quantity. Official Fractional Contracts still says the retail desk fills whole event contracts only. That is useful if you already have the authenticated access those pages describe. It is not permission to tell a US retail reader to open a developer portal, paste a key, or run a script — and it is not a reason to invent a Size tab on the US swipe.

Blocked and contested states

Reported unavailable as of June 2026: Arizona, Illinois, Massachusetts, Maryland, Michigan, Montana, Nevada and Ohio. That list is not a promise it stays still — litigation around sports event contracts in particular can narrow or shift access. If you are in a listed state, do not type a clip on the assumption the desk is open. If you are in Florida or another green-light state, still confirm the ticket appears and still accepts a typed amount before you leave size on the book.

Age is 18+ with identity verification. That is a different gate from the 21+ / responsible-gambling frame on our DFS pages, because these are traded financial instruments. If you also want NFL DFS, start at the picks hub — those contest-lock rules do not carry over. Compare platforms on the prediction-markets hub.

What you will not get from this page

A dollar welcome match, a paste-this promo code, a live bid, ask, or lot count, an invented Size / Shares / Contracts / Qty field the official US swipe pages do not print, a cloned limit-price / partial-fill / portfolio / cash-vs-buying-power / cancel-open-order / sell-filled-position / place-a-limit-order walkthrough, a newsletter form, or claim buttons for Kalshi, DraftKings, FanDuel, Underdog, Sleeper, PrizePicks, Hard Rock or BetRivers. We could not verify a standing official US welcome bonus on Polymarket’s own terms. Other publishers’ partner codes are theirs; we do not copy them. The honest user-facing line is still US access via CFTC-regulated QCEX — official Place a Trade says enter a dollar amount or Max, official Place a Trade does not reprint a Size field on the swipe we checked, official Fractional Contracts says a dollar amount buys whole contracts only and leftover returns to cash, official Glossary Size is posted depth on the book, official Orders & Trading says a limit is a price you set, this is not sportsbook or investment advice, and anything those public pages do not print is not a label or a number we invent. Last verified August 8, 2026.

Frequently Asked Questions

How do I set an order size on a new Polymarket US order?

Official Place a Trade and Official Order Placement: enter the dollar amount you want to trade, or tap Max to use your available balance, then review and swipe. Those pages do not reprint a retail field labelled Size, Shares, Contracts, Quantity, or Qty on the swipe we checked. We will not invent one. If public US help or the live card already shows that box, type how much you want this order to buy or sell before you confirm. Official Website vs App: US residents use the Polymarket US app, not polymarket.com. The only live claim on this page hops through /go/polymarket.

Where is the size field on Polymarket US?

On the new-order card — if the live screen prints it. Official Place a Trade reprints Yes or No, a dollar amount or Max, review, swipe. Official Glossary names trading contracts in quantities without reprinting a Size header on that swipe. If the live US card shows Size, Shares, Contracts, Amount, Quantity, or Qty, use that live word. If it only lets you type a number with no header, type the clip. Official Orders API Overview’s quantity is developer language, not a phone chip we will paste on the swipe.

Is order size the same as the limit price?

No. Official Orders & Trading: a limit is a price you set — the most you will pay on a buy, or the least you will accept on a sell. Official Place a Trade’s printed input is a dollar amount. Official Glossary: you trade contracts in quantities. Size is how many (or how many dollars). Price is the cents. How to set a limit price is that other number. This page does not clone it.

Do I type dollars or contracts?

Official Place a Trade reprints a dollar amount or Max. Official Glossary reprints contracts in quantities. Official Fractional Contracts: when you buy using a dollar amount, the desk purchases as many whole contracts as that amount can buy; leftover that cannot buy a full contract returns to cash. Official Liquidity teaching copy also names shares next to a dollar clip — that is help-center math, not a live board. If the live card shows one unit, use that live unit. We will not invent a Dollars / Contracts toggle those retail pages do not print.

Can I buy a fraction of a contract?

Official Fractional Contracts: Polymarket US does not support fractional contracts. All trades are executed in whole event contracts. A dollar amount that does not divide evenly leaves leftover cash in your balance. Official Orders API Overview’s quantity field can describe developer increments — that is not a retail chip, and it is not permission to type a fraction on the US swipe those retail pages do not offer.

Is glossary “Size” the same as the amount I type?

Not quite. Official Glossary: Size is the number of contracts available to buy or sell at a given price — posted depth on the book. Official Liquidity: that clip is resting orders other users left. The number you type is how much you are asking for. Official Price Impact: if your clip is larger than posted size at the best price, leftover can fill at worse levels. How to read liquidity names the book. This page is your clip.

Is this the same as setting a limit price, a partial fill, portfolio, or cash vs buying power?

No. Limit price is the cents you will pay or sell at. Partial fill is the middle state: some matched, leftover still open. Portfolio is the live open-position list after a fill. Cash vs buying power is what you can withdraw versus what you can still put on a new ticket. This page is only how to set how many shares — or how much dollar size — one new order asks for. We link out instead of cloning those click paths.

Is this the same as placing a limit order, canceling, or selling a filled position?

No. How to place a limit order is the broader rest / cancel / partial walk. Cancel open order is the undo on leftover size. Sell filled position is the exit on shares you already own. This page only teaches typing the clip. We do not clone those walks.

Is setting a Polymarket order size the same as picking a sportsbook stake?

No. Official What is Polymarket US / Official Prices & Market Data: Polymarket US runs a central limit order book. Other traders took the other side. A sportsbook stake is a house number you take or leave. See prediction markets vs sportsbooks if you wanted that parked hold. There isn’t one. Nothing here is sportsbook advice or investment advice.

Can I set a Polymarket order size in every US state?

No. As of our June 2026 check Polymarket was reported unavailable in Arizona, Illinois, Massachusetts, Maryland, Michigan, Montana, Nevada and Ohio. Florida is a green-light state. Sports markets are the most legally contested category anywhere. Confirm the ticket still appears and still accepts a typed amount before you rest size.

Which claim button is actually live on this page?

Polymarket only. The claim button hops through /go/polymarket. There is no /go/kalshi, DraftKings, FanDuel, Underdog, Sleeper, PrizePicks, Hard Rock or BetRivers claim here. We do not invent tracking URLs.

Is there a Polymarket order-size bonus or promo code on this page?

No. We do not publish a dollar welcome or a promo code. Partner codes that appear on other sites belong to those publishers. Confirm any live terms in the Polymarket US app. If you open Polymarket through our link we may earn a commission at no extra cost to you — that is not a user bonus.

Is setting a Polymarket order size the same as locking an NFL DFS contest entry?

No. Daily fantasy is a state-licensed gambling product — often 21+, with a 1-800-GAMBLER frame. Event contracts are CFTC-regulated financial/derivatives products, typically 18+ with KYC. A typed clip is not a contest lock, and a filled contract can still settle at zero. There is no protected bonus floor.

Advertising disclosure: Polymarket links are affiliate links — we may earn a commission at no cost to you, which never affects our ratings. Kalshi, DraftKings, FanDuel, Underdog, Sleeper, PrizePicks, Hard Rock and BetRivers have no live outbound claim on this page. Event contracts are CFTC-regulated financial products, not gambling. Trading involves risk and you can lose money, including your entire stake. Not investment advice. 18+. DFS pages on this site use a separate 21+ / 1-800-GAMBLER frame. Availability and terms can change — confirm current terms on Polymarket. Last verified August 8, 2026.