CRM API | REST API Integration

A good CRM is like the central nervous system of your business: the hub where all customer information converges—accurate and up‑to‑date. But what happens when multiple systems operate independently, isolated from one another? The answer is pretty simple: data chaos.

Sales teams waste time entering the same customer details twice. Marketing campaigns miss key customer insights. Support teams can’t see full purchase history. Undeniably, it’s unproductive, inconvenient, and, of course, expensive.

CRM APIs solve this problem by connecting your CRM to other business tools and turning fragmented data into a complete picture of each customer relationship.

What is a CRM API?

A CRM API is a set of rules and protocols that enables different applications to interact with your CRM system. It allows developers to build custom integrations with your marketing automation platforms, social media platforms, accounting software, and more to create a real-time API-enabled data exchange between your CRM and the other system that can be used to improve communication and relationships with customers, suppliers, shipping providers, and partners. EspoCRM offers a well-documented, open API that is freely accessible to developers.

How does it work?

EspoCRM is built on a REST API architecture, which works through a request-and-response logic. The systems use four simple HTTP methods to perform CRUD operations on records: GET, POST, PUT, and DELETE.

These methods interact with specific API endpoints, which in their turn correspond to a specific entity in the CRM system (contacts, accounts, calls, etc.).

The system responds and sends back information in JSON format for ease of use. JSON payloads specify the fields and data required to create, update, or delete records within the CRM system.

You can add another layer of automation to your integrations using webhooks. They allow other applications to subscribe to specific events happening inside EspoCRM. So whenever one of the specified events occurs in your CRM (it can be that a new contact is added or an opportunity status is updated), the system automatically sends relevant data to the subscribed application, triggering further actions.

Common Mistakes to Avoid in Conventional Integration Practices

Many companies choose conventional integration methods that cause more headaches than harmony. These conventional integration methods often involve manual data transfers or custom coding.

Manual data transfers

Using only manual methods to transfer data from some business applications to your CRM is a direct path to wasted time and often incorrect data. Just think of this vicious cycle of copying and pasting information, introducing typos and inconsistencies in random records. This method not only slows down your business operations and leads to data inaccuracy but also requires you to store the same data on several different platforms.

Custom coding

Custom coding can be an adaptable and attractive option at first glance, as it is fully adjusted to your business needs. Yet, maintaining it can pose challenges. Every new integration requires writing a lot of code, which then needs to be updated and fixed constantly by your in-house teams who could spend this time working on more important business projects. Custom integrations also create their own headaches; they consume your server space, often lead to issues with duplicate data, and leave room for human error and inconsistencies.

That’s why many businesses choose APIs instead. They’re tested, stable, and developer-friendly. No need to spend weeks coding and months maintaining, you can connect systems in hours and get back to building features that differentiate your business, as APIs offer faster setup, minimal maintenance, and more reliable results.

Understanding how EspoCRM’s API can help your business

Like many other platforms, EspoCRM can communicate with other applications via API. It uses a specific API architecture called REST API (that is short for Representational State Transfer API), which simplifies the integration of the CRM system with other apps. It offers a convenient and standardized way to interact with EspoCRM’s data, which simplifies the integration of EspoCRM with other systems. You can learn more about EspoCRM’s API in the official documentation here.

REST APIs leverage CRUD operations to ensure consistent data exchange. This acronym stands for 4 basic operations that can be performed on data in a database:

• Create to add new records using the POST method;
• Read to access to the existing records using the GET method;
• Update to change the existing records using the PUT method;
• Delete to remove the existing records using the DELETE method.

Let’s see how EspoCRM’s API can improve lead nurturing by syncing information to save employee’s time.

Creating records via API

If you’re using EspoCRM and some other platform for marketing or lead generation, you may often find yourself in a situation where you need to add new leads to your EspoCRM system. Assuming that you have previously made the necessary authentication setup, you can use the POST method to create a lead record in EspoCRM.

Here’s a basic example:

POST Lead { “firstName”: “John”, “lastName”: “Doe”, “email”: “john.doe@example.com”, “status”: “New” }

This code sends a POST request to the Lead endpoint, including the payload with essential details for a new lead record: first name, last name, email, and status. A successful response will return the newly created lead record within EspoCRM.

The same logic applies to creating other entities in EspoCRM via API. Simply replace “Lead” with the desired entity type (e.g., Account, Contact, Call) and adjust the payload with the relevant fields for that entity.

Updating records via API

As you continue to interact with your lead using your marketing tools, you can find out more information and might need to update this record in EspoCRM. To use API for updating, you need the PUT method.

Here’s a simple example of updating a lead’s website:

PUT Lead/{leadId} { “website”: “www.website_example.com” }

The PUT request targets the specific Lead using its ID. The payload includes only the updated website field. A successful response will change the website field with new data.

Creating relationships via API

Eventually, your lead purchased your product or service and was converted into a contact record. During your interactions, you found out that this contact (John Doe) works for ABCD company. You can use the API to create a relationship between your contact and the relevant account record.

Here’s how you can achieve this:

POST {entityType}/{id}/{link}

POST Contact/{contactId}/accounts { “id”: “{accountId}” }

This example shows sending a POST request to create a relationship between your contact and account within EspoCRM. The request contains the contact ID and the link of the related entity (accounts). In the payload, we specify the account ID of the record we want to link with the contact. If you need to link multiple account records, you can include several account IDs. A successful response will confirm that the relationship has been created.

Types of CRM Entities to Sync Using API

Every business requires information, especially customer-related information, to effectively manage sales and marketing initiatives. CRM systems use entities to store, organize, and manage different types of business data, like contacts, leads, deals, calls, etc. In this next section, we are going to take a closer look at the most common CRM entities that can be synchronized using APIs. It will help you to better understand how CRM APIs work and how you can use them for your business.

Leads

Lead is the entity that represents potential clients who have expressed some interest in your product or service. You can collect lead data from the web forms on your website, through networking, social media accounts, and other sources.

As a rule, lead information encompasses name, email, phone number, and interests. Businesses use this information to start nurturing relationships with leads and eventually convert them into paying customers. The principles of managing leads are similar to those of managing contacts.

Contacts

Contact is the entity that stores the information about your current customers, partners, and suppliers. Contact records include detailed information about a person covering contact details, email, addresses, notes, and even preferences or interests. You can use this entity to track your interactions and build business relationships with these people.

Accounts

Account is the entity that contains information about organizations and companies your business deals with. They can be linked with multiple contact records that will represent the people who work for this company (account). Accounts usually store such data as company name, website, industry, phone numbers, billing and shipping details, and so on. They help you manage and organize information about companies, including their contacts, opportunities, and history of interactions (calls, tasks, meetings) that are linked with account records through relationships between these entities.

Calls

Call is the event entity that stores information about phone call conversations with leads, contacts, and accounts. It usually includes such details as name, date start and date end, attendees, duration, and notes.

Meetings

Meeting is the event entity that tracks scheduled interactions like meetings, conferences, webinars, business lunches, or any other events involving leads, contacts, or accounts. Meetings store such details as name, date start and date end, attendees, duration, and status.

Tasks

Task is the entity that stores information about specific actions or activities that are related to leads, contacts, or accounts and are assigned to your team members. Task information usually encompasses name, priority, status, date start and date due, description, etc. These activities might involve follow-up emails, sending proposals, or scheduling meetings.

What is CRM Integration?

Many businesses struggle with fragmented customer data. The situations when your sales team can’t see customer emails and marketing has no clue about recent support interactions are not rare for businesses using several different apps. This is the reality of data silos – valuable customer information trapped in separate applications.

CRM integration helps to solve this issue. It is the process of connecting a CRM software system with third-party applications. In simple terms, it bridges the gap between email marketing platforms, accounting software, project management tools, call center systems and your CRM. It helps to prevent data isolation and provides your business the ability to manage various business applications through a single CRM platform.

Types of CRM API integrations

There are several ways to connect your CRM with other applications using APIs:

• Pre-built integrations

  Many CRM providers offer pre-built integrations for popular business apps. They are easy to set up and perfect for getting started quickly.

• Integrations through third-party apps

  These tools serve as connectors. They allow you to integrate your CRM with apps that may not have native integrations. It is a more flexible way than pre-built integrations but it may require additional costs.

• Custom-built integrations (using REST API)

  For complex needs or highly specific integrations, some businesses choose to build custom solutions using the CRM’s API. This integration type offers the most control but requires technical expertise.

CRM API user, why is it important?

EspoCRM offers several types of user records: regular users, admin users, API users, etc. Each user type serves its purpose. For example, regular users and admin users are designed for human interaction with the CRM interface and system management. They often have broader permissions and that’s why using them for API access is a security risk. Granting API the same access level as an admin user can provide external applications unrestricted access to your entire CRM data.

A secure and controlled way to integrate external applications with your EspoCRM is using API users. Designed specifically for accessing the system via its API, these users are granted access permissions governed by Roles. API User Roles define what data these external applications can access and what actions they can perform. They help you decide which apps are allowed to view, add, edit, or delete specific records and avoid giving them more access than they need.

What can I do with EspoCRM’s API?

EspoCRM’s API offers many ways to extend your CRM’s functionality by connecting it with your existing technology stacks. You can integrate and exchange data between the CRM solution and your communication platforms (Slack, Zoom, or Microsoft Teams), marketing tools (Mailchimp), or accounting software (Xero). That will result in less jumping between tools or copying data by hand and more time for building relationships and closing deals.

CRM API Developer Resources

Here’s what EspoCRM offers to help developers get started:

• API Documentation with detailed instructions on how to use and configure EspoCRM’s API for developers.

• Developer Community where you can communicate with other EspoCRM developers to get help or share your own experience.

• API Client on GitHub. It is an official EspoCRM API client library that can be used for the development of EspoCRM integrations.

Adhering to GDPR when using EspoCRM’s API

The EU’s General Data Protection Regulation has strict rules for handling personal data. Since APIs can deal with sensitive customer data, GDPR applies to CRM integrations as well.

If your EspoCRM instance stores, processes, or transfers personal information of EU citizens via an API between applications, ensure compliance with GDPR. When transferring personal data to third-party countries, you need to apply additional safeguards like signing Data Processing Agreements (DPAs) for third countries that have a suitable level of data protection confirmed by the European Commission (you can find the list here) and Standard Contractual Clauses (SCCs) for countries outside the approved list.

If your CRM API handles only non-personal data, GDPR restrictions are less strict. But regardless of data type, prioritizing data security is always good practice for building trust with customers.

Using Make for EspoCRM integrations

Make is a third-party platform that allows you to connect EspoCRM with hundreds of other applications. The tool offers an intuitive interface for building integrations that help to sync data and automate tasks like adding new leads and calls to your CRM from other platforms.

Using Zapier for EspoCRM integrations

Zapier is a third-party service that simplifies data exchange between different tools with EspoCRM. Similar to Make, it allows you to connect EspoCRM with various apps you use. With its help, you can streamline processes, like automatically sending invoices to customers after successful deals in EspoCRM, or adding new contacts to EspoCRM from your Google Sheets.