Using The New Companies API

Introduction

The Similarweb ‘Find New Companies’ API lets you receive real-time, webhook-based notifications whenever a new company matches one of your dynamic Saved Searches.

Instead of manually refreshing lists to spot newly qualifying prospects, the API pushes new matches directly to your endpoint the moment they are detected, giving your team a same-day outreach advantage across 100M+ websites tracked by Similarweb.

Key Benefits

Real-Time Discovery: Get notified instantly when a new company crosses your ICP thresholds, employee count, technology adoption, traffic, and more, without manually re-checking saved searches.
Webhook-Based Delivery: Push new matches straight into your existing workflows. Pipe webhooks into Salesforce, HubSpot, or any endpoint so new companies auto-create as scored, routed leads.
Cost-Transparent Model: Pay only 1 Data Credit per new company delivered. Monitor remaining credits through a visual meter on the Manage page.
Zero-Effort Prospecting: SDRs, AEs, and CSMs no longer need to manually enter the platform and check for new companies. New matches surface automatically for immediate action.

Where to Find It

The setup for ‘Find New Companies’ API is located under Integrations → APIs, in the same section as the existing Signals API and Contacts API.

A new card appears showing:

Webhook status: Configured or Not configured
Subscribed saved searches: count of active webhook subscriptions
New companies found recently: e.g., 49
“Manage” button to open the webhook configuration page

Pricing

The Find New Companies API is available for Business & Enterprise Sales Intelligence customers.

1 Data Credit per new company delivered. Credits are deducted automatically when a matching company is found and sent to your endpoint.

The cost is:

Subscribing & configuring webhooks: Free — no credits consumed.
Each new company delivered via webhook: 1 Data Credit (DC).

Important: Only Saved Searches with up to 100,000 companies are eligible for webhook subscriptions. This keeps the feature cost-effective and encourages well-targeted lists.

Setup & Configuration

Click “Manage” on the Find New Companies API card to open the configuration page. The page contains two sections:

1. Data Credits Card

Displays the cost model: 1 Data Credit per new company.

2. Webhook Configuration Card

Each row contains:

Field	Description
URL	Your webhook endpoint URL (e.g., https://webhook.site/abc123). Must be a valid HTTPS URL.
Saved Search	Dropdown of your dynamic Saved Searches. Lists over 100K are greyed out and labeled “(exceeds 100K)”.
Test	Sends a test payload to your URL to verify connectivity.
Delete	Removes the webhook subscription.

Click “+ Add another” to add additional rows.

How It Works

Step 1 — Configure

Navigate to Integrations → APIs → Find New Companies API → Manage. Add your webhook URL and select a Saved Search from the dropdown.

Step 2 — Test

Click the Test button to send a sample payload to your endpoint and verify it’s receiving data correctly.

Step 3 — Receive

When a new company matches your Saved Search criteria, Similarweb sends a webhook request to your configured URL in real time. 1 Data Credit is deducted per company delivered.

Step 4 — Act

Route the incoming data into your CRM, scoring model, or outreach tool.

Note: Webhooks only fire for new matches going forward. There is no historical backfill in v1.

Webhook Payload

When a new company matches your Saved Search, a POST request is sent to your configured endpoint with the following JSON payload:

JSON

{

"domain": "scrooppatterns.com",

"companyName": "Scroop Patterns",

"savedSearchName": "Yotpo ICP email marketing",

"webhookConfigId": "767b107d-2bc7-4374-8542-8e54a2a6344c",

"timestamp": "2026-04-13T12:51:07"

}

FAQs

Q: Does the webhook fire for companies already in my Saved Search?

A: No. Webhooks only fire for new matches going forward. Companies that already exist in your Saved Search at the time of configuration are not included. There is no historical backfill in v1.

Q: Can I use the same webhook URL for multiple Saved Searches?

A: Yes. You can point multiple rows to the same URL, each linked to a different Saved Search. The payload includes the saved search name so your endpoint can differentiate which list triggered the event.

Q: What happens if my Saved Search grows beyond 100K after configuration?

A: The webhook will continue to operate, and new matches will still be delivered even if the list exceeds 100K.

Q: How quickly are new matches delivered?

A: New matches are delivered in near-real time. Once a company is detected as matching your Saved Search criteria, the webhook fires within minutes.

Q: What if my endpoint is down when a webhook fires?

A: Similarweb retries delivery up to 3 times with exponential backoff. If all retries fail, the delivery attempt stopping.

Q: Can I add extra filters on top of my Saved Search?

A: Not in v1. The webhook uses the Saved Search criteria exactly as configured. Refine the Saved Search itself for more specific targeting.

Q: Are there in-app or email notifications?

A: Not in v1. Notifications are API/webhook only. In-app and email notifications may be added in a future release.

Q: How are Data Credits consumed?

A: 1 Data Credit is deducted each time a new matching company is delivered to your webhook endpoint. Subscribing and configuring webhooks is free. Monitor your credit balance via the visual meter on the Manage page.