Queue PositionFIFO
Queue position is your place in line among limit orders at the same price; orders placed earlier are usually filled first.
Queue position is your place in line among resting limit orders at the same price. On many venues the first order in is the first to fill, so changing an order can send it to the back. Matching rules vary by venue.
- Category
- Market Structure
- Reading time
- 3 min
- Also called
- Place in line, Time priority
- Updated
Queue position in plain words
Under first-in, first-out (FIFO) matching, orders at the same price are filled in the order they arrived — the first one in is filled first.1
FIFO looks only at price and time when deciding who gets filled.1
On some exchanges, an order loses its place and goes to the back of the queue if you raise its size, change its price or change its account.1
How queue position works
Price first
Better prices fill first.
Then time
At the same price, the earliest order is matched first.1
Track size ahead
Estimate shares queued before you.
Avoid needless edits
Avoid changes that reset your priority, such as increasing the size.1
Know icebergs
Know that iceberg refills get a new timestamp and rejoin the back of the queue.2
Check venue rules
Check your venue's rules — some use pro-rata or mixed matching instead of pure FIFO.1
Worked examples
Example 1 — Waiting in line
3,000 aheadHypothetical: 3,000 contracts ahead at 99.50; you add 10.
| Must trade first | 3,000 |
Under FIFO, the 3,000 shares ahead of you must trade before your order fills.1
Example 2 — Edit penalty
Re-queuedYou raise size from 10 to 20.
| Queue | Back of line |
Raising the quantity cost the order its place in line.1
Example 3 — Iceberg refresh
Back of lineA hypothetical iceberg shows 50 at a time.
| Each refresh | New time stamp |
Each refill comes with a new timestamp, so it goes to the back of the queue.2
FIFO vs pro-rata matching
| Aspect | FIFO | Pro-rata |
|---|---|---|
| Priority | Time at price | Size at price |
| Rewards | Being early | Being large |
| Edits | Can lose place | Less impact |
| Common in | Many stock and futures markets | Some rate futures |
Where queue position matters
Passive orders
Filling a Limit Order.
Scalping
Speed in Scalping.
Depth
Reading the Order Book.
Market makers
How a Market Maker earns spread.
Advantages and disadvantages
Advantages
- Rewards early, patient orders.
- Simple and transparent rule.
- Helps estimate fill chances.
Disadvantages
- Late orders may never fill.
- Edits can cost priority.
- Fast traders dominate queues.
- Rules vary by venue.
Going deeper
Read as far as you need. Each level builds on the one before it.
Common mistakes
Editing size up
You go to the back.
Ignoring size ahead
Estimate your place.
Assuming FIFO everywhere
Check venue rules.
Chasing price
Repricing resets priority.
Check your understanding
Test yourself before moving on. Each answer comes with an explanation.
Key points to remember
- Queue position is your place in line at a price.
- FIFO uses price then time.
- Some edits send you to the back.
- Hidden orders hide true queue size.
- Venues differ.
Frequently asked questions
Can I see my queue position?
Does reducing size lose priority?
Is FIFO used everywhere?
Further learning
- Limit Order
Resting orders.
- Order Book
Seeing the queue.
- Market Maker
Queue users.
- Time-in-Force: IOC, FOK and GTC
Order lifetime.
Sources
This article is written in our own words. The sources below support the specific facts, rules and figures marked with a number in the text. Links open the original publisher’s page.
- CME Group. Supported Matching Algorithms (opens in a new tab) Checked .
- Eurex Bonds. Eurex Bonds Market Model (opens in a new tab) Checked .
- Nasdaq. Nasdaq Order Types (opens in a new tab) Checked .
Educational content, not financial advice. Examples use hypothetical prices and simplified costs; actual fees, margin rules and regulations vary by broker, market and country. We are not affiliated with any publisher linked above. Last reviewed . Report an error or request a source credit.