Welcome to the Harvest API v1 Help Center

The V1 API has been deprecated, but will continue to function for legacy applications. As of January 1st, 2019, we will only offer technical support for the V2 API.

API Introduction

API V1 to API V2 Migration Guide
General Information
Using Who Am I
Supported Currencies

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Authentication

OAuth 2.0 Authentication
For Client Side Applications
For Server Side Applications

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Clients API

Add & Update Clients
Add & Update Client Contacts

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Invoices & Estimates API

Create An Invoice
Estimates API
Show & Update Invoices
Invoice Messages & Payments

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Expenses API

Add & Update Expenses
Expense Categories

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Timesheets API

Add & Update Time Entries
Retrieve Existing Time Entries

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Projects API

Create & Show Projects

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Reports API

Time Reporting
Expense Reporting

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Tasks API

Create & Show Tasks
Task Assignments

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Users API

Managing Users
User Assignments

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