Announcement of KuCoin UTA API V1 to V2 Upgrade

08/27/2026, 18:04:00

 
With the increasing requirements for API stability, security, standardization, and scalability in institutional and professional trading scenarios, KuCoin has conducted a comprehensive upgrade of its API system and launched the new API V2.
 
KuCoin UTA API V2 follows industry-standard API design principles and best practices, with systematic improvements to the API authentication mechanism, error code system, API specifications, and documentation structure. These enhancements provide developers with a more standardized and consistent API integration experience.
 
This upgrade will not affect the normal use of the existing V1 API. The V1 API will remain available and can continue to be used normally. Going forward, V2 API will serve as the primary API version for feature updates and maintenance, while V1 API will no longer have new feature updates.
 

1. Upgrade Schedule

The UTA API V2 upgrade is scheduled to take effect at:
2026-08-27 10:00:00 (UTC)
 

2. Upgrade Impact

This upgrade applies only to the UTA API and will not affect the normal use of the existing V1 UTA API.
  • The V1 API will remain available, and existing API integrations do not need to be adjusted immediately.
  • The V1 API will no longer have new feature updates. New features and future API optimizations will be dedicated for the V2 API.
  • Users are encouraged to gradually migrate to the V2 API to take advantage of the latest API features and specifications. Please refer to API Introduction.
 

3. Major Updates in V2 API

3.1 WebSocket Authentication Upgrade

The V2 API will adopt a new API authentication scheme. The authentication mechanism will be changed from Connect Token to Signature-based authentication.
The new authentication method provides a more standardized request verification mechanism.
For detailed authentication rules and Signature generation methods, please refer to WebSocket Introduction.
 

3.2 API Error Code Specification Upgrade

V2 APIs will adopt a brand‑new error code specification to implement unified and standardized management of API error codes.
For detailed error codes and error messages, please refer to API Error Code.
 

3.3 API Endpoint Updates

  1. The URLs of all UTA API V2 endpoints have been updated, and all endpoints have been upgraded to the V2 version.
  2. The following API parameters have been changed compared with V1:
 
Update Type
Endpoints
Update Info
[Modify]
UTA REST Get Account Currency Assets (Classic)
  • Rename response field: hold→ locked
 
[Modify]
 
UTA REST Get Sub Account Currency Assets
 
  • Rename request field: UID → uid
  • Update response structure and fields: accountList → accounts currencyList → currencies accountSubType → subAccountType liabilityPrinciple →liabilityPrincipal hold → locked
  • Remove documented response enum value: accountType: OPTIONS
[Modify]
UTA REST Flex Transfer
 
  • Replace request field: type → transferType with INTERNAL, PARENT_TO_SUB, SUB_TO_PARENT, SUB_TO_SUB
  • Replace optional request fields with required fields: fromAccountSymbol → fromAccountTag toAccountSymbol→ toAccountTag
 
[Modify]
UTA REST Get Deposit Address
 
  • Rename response fields: chainId → chain to → toAccountType
  • Response fields memo and remark are now optional
 
[Modify]
UTA REST Get Withdrawal Quotas
 
  • Rename request field: chainId → chain
  • Add request fields: withdrawType (required), isInner (optional)
  • Rename response fields: chainId → chain remainAmount → remainingQuotaAmount availableAmount → availableWithdrawAmount withdrawMinFee → minWithdrawFee innerWithdrawMinFee → minInnerWithdrawFee
[Modify]
UTA REST Get Currency
 
  • Change request field: currency is required now
  • Rename chain-level response field: chainId → chain
  • Add chain-level regex and fee fields: addressRegex, memoRegex, depositFeeRate, depositTierFee, fixedDepositFee, maxDepositFee, maxWithdrawFee
[Modify]
UTA REST Get Currencies
 
  • Update response structure and fields: items[] → list[] chainId →chain
  • Remove currency-level fields: isMarginEnabled, isDebitEnabled
  • Add chain-level regex and fee fields: addressRegex, memoRegex, depositFeeRate, depositTierFee, fixedDepositFee, maxDepositFee, maxWithdrawFee
[Modify]
UTA REST Get Fiat Price
 
  • Change request fields: base is required now currencies changed from a comma-separated string to a string array
[Modify]
UTA REST Get Symbol
 
  • Add response fields: maxMarketOrderSize, preMarketToPerpDate
  • Update response enums: tradingStatus values: TradingEnabled, TradingDisabled, Init, Open, PrepareSettled, BeingSettled, Settled, Paused, Closed, CancelOnly feeCategory: 1, 2, 3 → classA, classB, classC
  • Update response field types: callauctionFirstStageStartTime, callauctionSecondStageStartTime, callauctionThirdStageStartTime, expiryTime, settlementTime, maxLeverage
[Modify]
UTA REST Withdraw
 
  • Rename request field: chainId → chain
[Add]
UTA REST Amend Order & UTA Websocket Amend Order
  • New endpoint
 
[Modify]
UTA REST Get Order Details & Get Order History
  • Response field cancelReason returns an enum value instead of a descriptive cancellation reason. Changes have been applied to both UTA API V1 and V2.
[Modify]
UTA REST Get Trade History
 
  • Add request field
fillType: support to query all kinds of trade types
[Modify]
 
UTA Websocket Funding Fee
 
  • Add new request field symbols to support subscribing multiple symbols and new response field lfrrepresenting last funding fee rate (corresponding to the last settlement time).
[Add]
UTA Websocket All Funding Fee Rates
  • New endpoint
 
[Add]
UTA REST Get Current Funding Rate
  • New endpoint. Get current Futures funding rates by contract symbol or product type.
[Modify]
UTA REST Get Index Price
  • Fix symbol in/out .KXBTUSDT → XBTUSDTM.
[Modify]
UTA REST Get Interest Rate Index
  • Add standard XBTUSDTM to in-param
[Modify]
 
UTA REST Get Klines
 
  • Add klineType to replace symbol suffix encoding; strip suffix from symbol (backward compatible); Symbol Naming Standard set to govern future interfaces.
 

3.4 Rate Limit Rules for V1 and V2

  • Requests made through the V1 and V2 APIs will consume the corresponding rate limit pool quota collectively.
  • Upgrading to V2 will not provide an additional rate limit quota independent of V1.
  • Users should reasonably manage the request frequency of V1 and V2 APIs based on their actual API usage.
 

4. API Documentation Contents Update

To help users distinguish between different API versions, we have also updated the API documentation structure.

4.1 V1 API

The existing V1 API endpoint content has been moved to the "Abandoned Endpoints" content. Please refer to the Abandoned Endpoints content.
The V1 API is still available for use. If you need to view or continue using the V1 API, please access the relevant endpoint documentation under this content.

4.2 V2 API

The new V2 API endpoints have been added to the corresponding API product and business category contents.
Users are recommended to prioritize the corresponding V2 API endpoints and documentation when referring to the API documentation going forward.
 

5. V2 API Migration Guide

5.1 New Users

If you are integrating with the KuCoin API for the first time, we recommend using the UTA Mode + UTA API V2 as your API integration solution.
You can refer directly to the UTA REST and UTA WebSocket documentation.
 

5.2 Migration Guide for Existing Users

Existing users can gradually migrate their existing endpoints to V2 based on their business requirements. During the migration process, we recommend following the steps below:
  1. Adapt to the New Authentication Method
Implement the WebSocket V2 Private Channels and Trade authentication based on Signature-based authentication.
 
  1. Batch Endpoint Migration
You can first review the Changelog entries published on and after August 27, 2026 and identify the endpoints listed in the Changelog.
For endpoints that are not listed in the Changelog, no changes to the existing business logic are required. You can directly replace the V1 API URL with the corresponding V2 API URL to complete the batch migration.
 
  1. Migrate Specific Endpoints
For endpoints listed in the Changelog entries published on and after August 27, 2026, specific changes have been made to the V2 API compared with V1.
Please adapt your integration according to the changes described in the Changelog, or refer directly to the corresponding V2 API documentation to complete the migration.
 
  1. Adapt to V2 Error Codes
The V2 API introduces a new error code specification and provides more standardized and specific error messages.
If your existing system performs programmatic processing based on V1 error codes, you will need to update your implementation to support the V2 error codes accordingly.
For details, please refer to API Error Code.
 

6. Migration Timeline

We recommend that existing V1 API users start migrating to V2 as early as possible.
Although the V1 API will remain available after the V2 launch, V1 will no longer receive new feature updates or endpoint optimizations. New API capabilities will be provided primarily through V2 going forward.
The V1 API is currently expected to be deprecated and taken offline on December 31, 2026. The specific sunset date and arrangements will be subject to subsequent official announcements.
 
 
For more information about the API, please join the official
KuCoin API Telegram Community.
You may also contact us via email at: api@kucoin.com