HighLevel API Ultimate Guide 

The HighLevel API is essential for most users who want to connect the platform to external tools.

If you're new to HighLevel, this might sound a bit techy or confusing.

HighLevel is an all-in-one platform with most of the tools you might need as a creator or business owner.

But it’s likely not the only tool in your tech stack — and integrating it with others can seriously boost its value for you or your clients.

Before diving into use cases, let’s take a look at what the HighLevel API actually does.

HighLevel has transitioned from the legacy v1 API to a newer OAuth 2.0 version — a more modern and secure standard that also offers granular control over permissions, unlike the static API keys used in v1.

The OAuth 2.0 authentication flow involves several steps:

• App Registration: A developer first registers the application in the HighLevel Developer Marketplace, defining the necessary details and permission scopes.

• User Authorization: The user (a location or agency admin) is directed to an authorization URL where they log in and grant consent to access data.

• Authorization Code: After successful authorization, the user is redirected to a predefined URI with a temporary authorization code.

• Token Exchange: The app exchanges this code for an access token and a refresh token via an API call.

• Token Expiry & Refresh: Access tokens typically last one day. Apps must use the refresh token (valid for one year and renewed on use) to keep the session alive without requiring user re-authorization.

Maintaining this token refresh logic is essential for consistent API access.

HighLevel recognized that this level of setup could be overwhelming for average users — so they introduced Private Integrations.

This feature provides a middle ground: it’s more secure than using raw API keys, but easier to implement than full OAuth 2.0 flows.

Private Integrations allow users (at both agency and sub-account levels) to generate scoped tokens directly from account settings.

These tokens allow you to restrict permissions — just like in OAuth — limiting the access a developer or third-party tool has.

Main API Endpoints

These are the key types of data and actions the HighLevel API gives you access to:

• Contacts: Create, read, update, delete contact records

• Calendars: Manage appointments, team schedules, and services

• Campaigns: Interact with marketing campaigns

• Opportunities & Pipelines: Manage deals and leads in your sales funnel

• Forms & Surveys: Access and submit form/survey data

• Messaging & Conversations: Interact with conversations (v2 has more granular control)

• Tasks & Notes: Create/manage tasks and notes tied to contacts or deals

• Users & Locations: Manage users and sub-account settings (especially via agency-level access)

• Workflows: Trigger or interact with automation workflows

• Custom Fields & Values: Manage additional data tied to contacts or other objects

Workflow Automation

If you’re using another platform for communication (like email or SMS), you can trigger workflows across tools.

• A new purchase in HighLevel could trigger an onboarding sequence in another platform.

• A Calendly or Acuity booking could trigger a reminder sequence inside HighLevel.

• You could sync contact data from another CRM into HighLevel or vice versa.

Task Management & Notifications

Another common use is keeping your internal team up to date.

If you’re using task tools like Asana, ClickUp, or Monday, you can:

• Automatically create and assign tasks when something happens in HighLevel.

• Send notifications to your team on Slack, Telegram, or WhatsApp.

This way, your team doesn’t need direct access to HighLevel — but still stays in the loop.

Analytics & KPIs

While HighLevel offers built-in analytics, many businesses use external tools for reporting.

You can:

• Pull data into Google Sheets to create forecasts or dashboards.

• Centralize your KPIs across all platforms in one place.

If you skipped the technical stuff or just want quick answers — here are the most common questions:

Does HighLevel offer a free API? 

You get basic API access on the Starter plan ($97/month). For full functionality and OAuth 2.0 support, you’ll need to upgrade to the Unlimited plan ($297/month).

How do I authenticate with the Basic API (v1)? 

Here’s the simplified flow:

1. Go to Settings > API Keys

2. Copy the API key

3. Add it to the request Header in your API call

Can I use Zapier with HighLevel’s API? 

Yes — you can integrate HighLevel with Zapier on any paid plan.

You can even connect individual sub-accounts, which is useful for client-based businesses or to maintain separation for privacy.

Is HighLevel’s API suitable for enterprise use? 

Yes — the OAuth 2.0 version meets modern security standards.

Just note: for full access and flexibility, you’ll need the Unlimited Agency Plan.