New Order
Submit new orders as New Order Single with MsgType (35) set to D.
Identity Mapping
| Paxos API Field | FIX Tag |
|---|
customer_id | Account (1) |
profile_id | ClientID (109) |
Key Field Rules
- Account (
1) is your Paxos customer_id and ClientID (109) is your Paxos profile_id.
- Price (
44) must be omitted for Market (1) and Stop Market (3) orders.
- CashOrderQty (
152) is required for market buy orders and represents the fiat notional to convert.
- OrderQty (
38) is required for market sell, stop market sell, stop limit sell, and all limit orders.
- Send only one of OrderQty (
38) or CashOrderQty (152).
- StopPx (
99) is required for stop market and stop limit orders. Currently only sell stop loss orders are supported.
- HandlInst (
21) must be set to 1.
- Symbol (
55) must be the currency pair, and SecurityType (167) must be FOR.
Supported Order Types
We support the following OrdType (40) values:
| Order type | OrdType (40) |
|---|
| Market | 1 |
| Limit | 2 |
| Stop Market | 3 |
| Stop Limit | 4 |
2) orders with ExecInst (18) set to 6 (Post-Only).
Time In Force
Time in force is set with TimeInForce (59):
TimeInForce (59) | Meaning |
|---|
1 | Good Till Cancel (GTC) |
3 | Immediate or Cancel (IOC) |
4 | Fill or Kill (FOK) |
6 | Good Till Time (GTT) |
Order type (OrdType 40) | Allowed TimeInForce (59) | Default |
|---|
Limit (2) | 1, 3, 4, 6 | 1 (GTC) |
Market (1) | 3 | 3 (IOC) |
Stop Market (3) | 1, 6 | 1 (GTC) |
Stop Limit (4) | 1, 6 | 1 (GTC) |
6), include ExpireTime (126) in YYYYMMDD-HH:MM:SS or YYYYMMDD-HH:MM:SS.sss (milliseconds are ignored).
Tick Size Requirements
Price (44) must align to market tick sizes for limit and stop limit orders:
| Market | Tick size | Requirement |
|---|
| XBT markets | 0.25 | Price (44) must be evenly divisible by 0.25 |
| ETH markets | 0.05 | Price (44) must be evenly divisible by 0.05 |
| All other markets | 0.01 | Price (44) must be evenly divisible by 0.01 |
Order Routing Mode
Use OrderRoutingMode (8000) to choose the routing strategy for the new order.
OrderRoutingMode (8000) | Routing strategy |
|---|
1 | Standard |
2 | Best Execution |
OrderRoutingMode enables Paxos Best Execution routing on eligible accounts. To confirm availability for your integration, as well as learn more about the Best Execution mode, please contact your Paxos account representative.
If an invalid value is provided for OrderRoutingMode (8000), the field is ignored and the default routing mode configured for the customer is used.
Maximum Notional Order Size By Type
Maximum notional limits are based on OrdType (40):
Order type (OrdType 40) | Markets | Max notional (USD) |
|---|
Limit (2) | XBTUSD, ETHUSD | 1,500,000 |
Limit (2) | All other markets | 1,000,000 |
Market (1) | All | 500,000 |
Limit Order Taker Price Protection
Limit orders will be rejected if the order is taker and the Price (44) deviates by 15% or more from the midpoint.
- Text (
58) = InvalidPriceForTakerOrder
- OrdRejReason (
103) = 0 (Broker option)
See Execution Report - Order Reject for the full response format.
Standard FIX Fields (All Order Types)
| Tag | Field | When to Include | Notes |
|---|
8 | BeginString | Always | Standard FIX header |
9 | BodyLength | Always | Standard FIX header |
35 | MsgType | Always | D (New Order Single) |
49 | SenderCompID | Always | Standard FIX header |
56 | TargetCompID | Always | Standard FIX header |
34 | MsgSeqNum | Always | Standard FIX header |
52 | SendingTime | Always | Standard FIX header |
Standard FIX Trailer
| Tag | Field | When to Include | Notes |
|---|
10 | CheckSum | Always | |
Common Order Fields (All Order Types)
| Tag | Field | When to Include | Notes |
|---|
11 | ClOrdID | Always | Client order ID (a-z, A-Z, 0-9, ., -, _, $, :) |
109 | ClientID | Always | Paxos profile_id |
1 | Account | Always | Paxos customer_id |
21 | HandlInst | Always | Must be 1 |
55 | Symbol | Always | Currency pair |
167 | SecurityType | Always | Must be FOR |
54 | Side | Always | 1 = Buy, 2 = Sell |
60 | TransactTime | Always | |
Market
Limit
Stop Market
Stop Limit
Set OrdType (40) to 1 (Market). Price (44) must be omitted. See Time In Force and Maximum Notional Order Size By Type.Required| Tag | Field | When to Include | Notes |
|---|
40 | OrdType | Always | 1 (Market) |
| Tag | Field | When to Include | Notes |
|---|
152 | CashOrderQty | Market buy | Fiat notional to convert |
38 | OrderQty | Market sell | Base quantity |
| Tag | Field | When to Include | Notes |
|---|
59 | TimeInForce | To override default | Market orders default to 3 (IOC) |
2362 | SelfMatchPreventionID | If enabled | Requires additional permissions |
5047 | AllocBrokerAccountID | Brokerage clients | IdentityAccountId |
50 | SenderSubID | Brokerage clients | IdentityId |
5074 | FundCommissionOption | Brokerage clients | |
8000 | OrderRoutingMode | If enabled | 1 = Standard, 2 = Best Execution |
Set OrdType (40) to 2 (Limit). See Tick Size Requirements, Maximum Notional Order Size By Type, and Limit Orders.Required| Tag | Field | When to Include | Notes |
|---|
40 | OrdType | Always | 2 (Limit) |
44 | Price | Always | Must meet tick size |
38 | OrderQty | Always | Base quantity |
| Tag | Field | When to Include | Notes |
|---|
18 | ExecInst | Post-only limit | Set to 6 |
126 | ExpireTime | If TimeInForce = 6 | See Time In Force |
| Tag | Field | When to Include | Notes |
|---|
59 | TimeInForce | To override default | Limit orders default to 1 (GTC) |
2362 | SelfMatchPreventionID | If enabled | Requires additional permissions |
5047 | AllocBrokerAccountID | Brokerage clients | IdentityAccountId |
50 | SenderSubID | Brokerage clients | IdentityId |
5074 | FundCommissionOption | Brokerage clients | |
8000 | OrderRoutingMode | If enabled | 1 = Standard, 2 = Best Execution |
Set OrdType (40) to 3 (Stop Market). Only sell stop loss orders are supported.Required| Tag | Field | When to Include | Notes |
|---|
40 | OrdType | Always | 3 (Stop Market) |
99 | StopPx | Always | Stop price |
38 | OrderQty | Always | Stop Market sell quantity |
| Tag | Field | When to Include | Notes |
|---|
126 | ExpireTime | If TimeInForce = 6 | See Time In Force |
| Tag | Field | When to Include | Notes |
|---|
59 | TimeInForce | To override default | Stop Market defaults to 1 (GTC) |
2362 | SelfMatchPreventionID | If enabled | Requires additional permissions |
5047 | AllocBrokerAccountID | Brokerage clients | IdentityAccountId |
50 | SenderSubID | Brokerage clients | IdentityId |
5074 | FundCommissionOption | Brokerage clients | |
8000 | OrderRoutingMode | If enabled | 1 = Standard, 2 = Best Execution |
Set OrdType (40) to 4 (Stop Limit). See Tick Size Requirements.Required| Tag | Field | When to Include | Notes |
|---|
40 | OrdType | Always | 4 (Stop Limit) |
44 | Price | Always | Must meet tick size |
99 | StopPx | Always | Stop price |
38 | OrderQty | Always | Base quantity |
| Tag | Field | When to Include | Notes |
|---|
126 | ExpireTime | If TimeInForce = 6 | See Time In Force |
| Tag | Field | When to Include | Notes |
|---|
59 | TimeInForce | To override default | Stop Limit defaults to 1 (GTC) |
2362 | SelfMatchPreventionID | If enabled | Requires additional permissions |
5047 | AllocBrokerAccountID | Brokerage clients | IdentityAccountId |
50 | SenderSubID | Brokerage clients | IdentityId |
5074 | FundCommissionOption | Brokerage clients | |
8000 | OrderRoutingMode | If enabled | 1 = Standard, 2 = Best Execution |
