Update leads via API | ReactIn Help Center

Already added a lead and need to change its data later, fix a typo, attach a fresh custom variable, or push an updated email from your CRM? The Update Lead API lets you patch an existing lead in place, without creating a duplicate.

✅ What you'll need before you start

Before using this API, make sure you have:

Your Organization ID, List ID, and API Key
The lead's id you want to update, or the linkedinUrl you imported it with

📘 👉 Not sure how to get your API credentials? Follow this guide

💡 You get a lead's id from the Get Leads endpoint (the id field on each lead), or from the response of the Add Lead call.

🔗 API Endpoint

Send a PATCH request to this endpoint to update a lead:

PATCH https://app.reactin.io/api/[organizationId]/lists/[listId]/leads

🔐 Authentication & Headers

Header	Value	Description
Authorization	`YOUR_API_KEY`	Your secret API key from ReactIn
Content-Type	`application/json`	Required for all requests

🔒 Keep your API key private and only use it from secure backend code, never from the browser.

🧾 What to include in your request (Body)

Identify the lead with either leadId or linkedinUrl. Every other field is optional, send just the ones you want to change. This is a true partial update: fields you omit are left untouched.

Field	Required	Description
`leadId`	Yes*	The `id` of the lead you want to update (*or `linkedinUrl`)
`email`	Optional	New email
`firstName`	Optional	New first name
`lastName`	Optional	New last name
`linkedinUrl`	Yes*	With `leadId`: the new LinkedIn profile URL. Without `leadId`: the LinkedIn URL of the lead to update (*required if no `leadId`)
`companyName`	Optional	New company name
`customVariable1-5`	Optional	Any custom variable to add or overwrite

🔗 Update by LinkedIn URL: when leadId is omitted, ReactIn looks the lead up in the list by its linkedinUrl (www. and trailing slash don't matter). Handy to fix a variable you got wrong on import: resend the same linkedinUrl with the corrected fields. If several leads of the list match that URL, the call fails with 409, use leadId instead.

⚠️ Updating a lead resets its enrichment status, so ReactIn will try to auto-enrich it again with the new data. It also fires the LEAD_UPDATED webhook if you have one connected.

🧪 Example (JavaScript)

await fetch("https://app.reactin.io/api/[organizationId]/lists/[listId]/leads", {
  method: "PATCH",
  headers: {
    'Content-Type': 'application/json',
    'Authorization': 'YOUR_API_KEY'
  },
  body: JSON.stringify({
    leadId: 'lead_a1b2c3',
    email: 'john.doe@newcompany.com',
    companyName: 'New Company',
    customVariable1: 'Renewed'
  })
});

Or, without the leadId:

await fetch("https://app.reactin.io/api/[organizationId]/lists/[listId]/leads", {
  method: "PATCH",
  headers: {
    'Content-Type': 'application/json',
    'Authorization': 'YOUR_API_KEY'
  },
  body: JSON.stringify({
    linkedinUrl: 'https://www.linkedin.com/in/johndoe/',
    customVariable1: 'Corrected icebreaker'
  })
});

🧾 Response format

{
  "success": true,
  "id": "lead_a1b2c3"
}

🚫 Common Errors

Code	Description
400	Bad request, neither `leadId` nor `linkedinUrl` is provided
401	Unauthorized, invalid or missing API key
404	Not found, the list or the lead doesn't exist in your organization
409	Conflict, several leads of the list match this `linkedinUrl`, use `leadId`
429	Too many requests, rate limit exceeded
500	Internal server error, try again later

💡 Best Practices

🔎 Fetch the lead's id from the Get Leads endpoint before updating
✂️ Only send the fields you actually want to change
🔐 Keep your API key private, use a backend server or proxy
🔁 Add retry logic for occasional network or server errors

💡 Pro tip: Because updates re-trigger enrichment, batching several changes into a single PATCH is cheaper than sending one request per field.