eSign API & Developer Hub

Integrate eSign’s API eSignature software for a smoother digital experience for you and your customers. Get in with us today to request sandbox access.

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Request and Manage Electronic Signatures

eSign's API lets you customise and extend the functionality of your apps to meet your unique business needs. Create efficiencies with our API and SDK's, guided by our comprehensive developer documentation guides and code samples.

Connect eSign to your software and enhance agreement automation. Some of the features include: Signing of documents, request signatures from multiple parties, document process automation, multi-factor authentication and live document tracking.

1.1 million
documents processed per month
20,000
new signers per month
400,000
envelopes sent per month
1.1 million
documents processed per month
20,000
new signers per month
400,000
envelopes sent per month

API connects your business processes.

What is an API?

An Application Programming Interface, or API, is a software intermediary that allows multiple applications to communicate with each other. An API connects your business processes, services, content, and data to channel partners, internal teams, and independent developers in an easy and secure way.

APIs are quickly becoming the de facto standard by which companies exchange data and build consistent cross-channel customer experiences. Make sure your business stays ahead of the curve with eSign’s API technology.

Developer Guides
What is an API?

Greater flexibility and convenience.

Why Use API?

An API provides customers with an assortment of well-integrated features, providing greater flexibility and convenience that’s ideal when requesting digital signatures.

APIs integrate a number of different application functions into one big software program, making these applications more accessible and user-friendly for you and your customers.

What is an Electronic Signature

Compliant with all major eSignature laws.

Secure API with Simplified Management

When you choose an API service from eSign, you can be sure that your API is secure and compliant.

Our eSign platform and electronic signatures are compliant with all major eSignature laws and operate an encrypted client library for end-to-end encryption to protect the contents of your documents and your sensitive data.

Secure API Management

Easy to use eSign.

API Documentation

We want to make using the API as easy as possible, to help you integrate we’ve created the developer hub for eSign customers.

Here you can find all the essential links to documentation and reference code as well as our latest SDK’s and Tools.

API Reference
eSign API Documentation

Business Benefits of API

Increased Efficiency
Greater Automation

By using an API, you have the ability to integrate greater automation into your processes for a smoother, more efficient digital experience.

User Friendly Platform
Integrated Applications

With an API, you can effortlessly integrate numerous applications into one, simplified software.

Service Level Agreement
Smooth Customer Experience

By integrating your applications, you can equip your customers with a user-friendly and joined up website experience.

Elimate Human Error
Eliminate Barriers to Your Business

Remove any barriers between your customers and business with an integrated API and encourage greater traffic through flexible and convenient functionality.

Increased Security
Secure API

With the eSign platform, you can be sure all your data and communications are secure and compliant.

Reduce Filing
Build on Existing Systems

Using eSign’s API, you can create an integrated process on existing or new applications to innovate your current processes.

Testimonials

multivac-esign-customer

Mid Devon District Council

“Using eSign has made our tenancy completion processes so simple. You don’t have to be technically savvy to be able to use the platform and it doesn’t draw on any other ICT resources. Our tenancy agreements and documents are signed within minutes and we’ve even had tenants’ comment on how easy it is to use as a signer which is fantastic.”

Lisa Harber | Team Leader 
Portsmouth Testimonial

Portsmouth University Hospitals

“E-Sign has proven to be a fantastic system that has had an important positive impact on our homecare prescription services. It has enabled us to significantly reduce the administrative burden on clinicians, creating a lean process that allows prescriptions to be signed and completed within minutes rather than days. The combination of E-Sign and our new prescription management platform has transformed our workflows, allowing us to improve the service we provide. A patient’s health is at the end of each document and E-Sign has helped us ensure that every document is processed quickly, securely, and accurately.”

Raghu Mamullapally | Lead Pharmacist Homecare Services
Leicester Hospital Case Study

University Hospitals of Leicester

“We have seen significant improvements in our pharmacy service efficiency since implementing E-Sign. The platform is user-friendly and has allowed our team to securely and reliably provide prescriptions for crucial patient medication, minimising the risk of supply disruption and saving valuable time. Collaborating with E-Sign has been an easy process, Desi and Luke have always been professional and approachable to offer support when needed.”

Amy Page | Kidney Pharmacy Team
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University of Oxford

“The University of Oxford have appointed eSign UK Ltd. as their preferred electronic signature platform. eSign quickly guided departments on the most cost-effective and efficient route offered, providing continued support to ensure contracts were completed and deadlines met.”

Purchasing Department | End User
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Paratus Law

“The law supports the use of electronic signatures, and eSign is an essential tool for any business wishing to enhance customer experience and accelerate revenue. Esign is incredibly user-friendly, and using it has been a very positive experience both for me and for my clients.”

Simon Arthur | Owner
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Beyondly

“eSign has transformed our operations at Beyondly. Integrating eSign into our systems was relatively straight forward and has massively improved customer and team experience. As a Bcorp organisation we place high value on our environmental impact and since inception, eSign has represented a 31.46kg saving of CO2 entering the atmosphere.”

Emily Rice | Operations Manager
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National Clinical Homecare Association

“The tools are very easy to set up and intuitive to use. When we encountered issues, the eSign team was agile enough to respond, usually on the same day. The copy template feature has made setup with new customers much easier.”

National Clinical Homecare Provider | End User
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Slater Heelis Solicitors

“eSign is an invaluable tool that assists us in keeping track of our legal matters. It gives us full control of the document journey and has greatly improved signature capture and document turnaround times.”

Slater Heelis Solicitors | End User
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Morgan Ash

“Working in the regulated financial and medical markets we need a quick secure and economical signature process. eSign gives us all of these.”

Andrew Gething | Managing Director
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Blue I Properties

“Can’t recommend esign enough. It is quicker, easier and cheaper to use than many of their competitors.  The detailed Document History provides useful evidence and proof of when your document was created and signed.  Their team members are extremely knowledgeable of the systems, friendly and professional.  All in all, an amazing product at a very competitive price.”

Debbie Collins | Lettings Administrator
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Government Property Agency

“One thing which sets eSign apart is their flexible signature packages, allowing flexibility in both pricing and usage to provide the best solution for the organisation. The GPA has been very well looked after by our eSign account manager and we look forward to continuing our relationship with them.”

Government Property Agency | End User
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10-100

“The solution was simple to use, has a great management portal, and the price met our expectations. We now use the product for our own internal use and have recommended and deployed it into our customers when we get requests for signature solutions. eSign’s ongoing support is excellent, and they are continuously improving and developing their solution.”

Paul Visagie | IT Consultant
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Cambridgeshire County Council

“eSign has brought both time and efficiency benefits to our department since we started using the platform two years ago. It is easy to use and they have useful training videos available which have been helpful for training our team on how to use the platform and its features.”

Wendy Ballard | End User
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Churchill Support Services

“Using eSign has significantly reduced the time it takes to send and receive contracts which means we close deals quicker. I especially like how you can redirect and edit documents without creating new envelopes and keep track of which contracts are pending signature as an admin. As an environmentally friendly business, it’s helpful to see how much carbon we are saving with the carbon counter. I would definitely recommend eSign to a business who is looking to close deals faster.”

Katie Butcher | Client Relationship Manager
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University of Salford

“We use eSign at the University of Salford to issue copyright declaration forms when supplying copies of material to users of our archives. We used to issue the forms as attachments to emails, but users found it difficult to sign and return the forms, especially if they didn’t have a printer. Sending the forms using eSign has made it much easier and quicker for our users to sign and return the forms. From our end it is simple and straightforward to issue the forms via eSign and we get a notification when they have been completed.”

End User | University of Salford
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Polden Bower

“We wanted a user-friendly system that would comply with finance policy, manifest maximum engagement from all Signatories, and had the capability to offer more as we grow as an organisation.  eSign fits the bill on all fronts for us from affordability, cost savings, accessibility and functionality perspectives, right through to tried and trusted customer service, support and data security.  We spent our first year on the Business Plan to embed this new way of working into our processes and we are now ready to roll out eSign access to other Central departments as we upgrade to the Enterprise subscription.  The user guides, chat facility, training offer and support provided by eSign is all really helpful and the team are always responsive when we get in touch.  It’s also reassuring that the Data Centres are in the UK and are managed by eSign.”  

Alison Sanders | Executive Finance Officer
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Boon Brokers

“E-Sign has significantly helped our operations at Boon Brokers. Previously, clients had to manually print, sign, and scan documentation back to us. With the help of E-Sign’s API, we have managed to integrate the system into our software. This now enables all clients to easily E-Sign our fact-finds within a matter of clicks via e-mail. This has significantly improved the efficiency of our business. Thank you, E-Sign.”

Gerard Boon | Managing Director, Boon Brokers
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Thula

“We are very proud and thrilled to be working with the eSign team, creating a truly digital and revolutionising management tool for controlled drugs in a post-pandemic world. The benefits to the clinical and pharmacy teams are huge and drives greater legislative and regulatory confidence and safer and efficient patient care.”

Adele McAllister | Manager
Hessington Health Testimonial

Hessington Health

“Hessington Health is a busy national health screening and occupational health practice with over 18 independent schools and over 10,000 staff members. The challenge we have faced is reminding employees to sign consent forms before we release the reports to their employers. This is an incredibly time consuming process. E-Sign has offered us the perfect solution. The online dashboard allows us to track the consent forms in their journey, Set reminders and have a safe place to store the completed forms. This has saved us an immense amount of time and improved our governance in this area. It also allows the user to create bespoke forms meaning any organisation from any sector will be able to utilise this package.”

Harjeev Rai | Medical Director

Feature Examples

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Signature workflow via Iframe

Use eSigns iframe functionality to generate envelopes from within your own system.

LEARN MORE
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One Click Send And Sign

Generate and sign an envelope in one click using API.

LEARN MORE
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Use OAuth 2 To Get Data

Retrieve account data using eSigns OAuth functionality.

LEARN MORE

Looking to test our API? Request sandbox access today.

The API is available to trial for 14 days, sign up up today and request an API token by providing your email address below today or contact us for more details.
Request Sandbox Access
Free Electronic Signature Trial

CHOOSE YOUR TEMPLATE TO SUIT YOUR BUSINESS NEEDS

Templates

eSign templates simplify document signing for your business, saving time and resources. Easily integrate electronic signatures into your workflow, whether it’s contracts, agreements, or other legal documents.

View eSign Templates
eSign Templates Free
eSign Graphic Designer Contract Template
eSign Business Contract Proposal Template
eSign Model Agreement Tenancy
Graphic Design Proposal Template

eSign Case Studies

National Clinical Homecare Association Case Study
National Clinical Homecare Association

The healthcare industry clearly recognised the need to adopt a digital approach to prescription processing, giving operational advantages, regulatory compliance and improvements to patient safety.

LEARN MORE
Mid Devon Case Study
Mid Devon District Council

There has been significant time and cost savings on the sign-up process for new tenants as there is no longer a requirement for officers or tenants to travel to meet in a location to sign the agreement. 

LEARN MORE
Leicester Hospitals eSign Case Study
University Hospitals Leicester

The E-Sign implementation has achieved demonstrable improvements in service efficiency, supported cross-site working and reduced costs for the UHL Kidney Pharmacy home delivery services.

LEARN MORE

Flexible eSignature Process

Seamless Integration

eSign integrates with leading software platforms to improve and simplify your transaction.

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eSign Connects and Integrates Applications

Featured Industries

Discover eSignature solutions and use cases in your industry.

Healthcare

eSign offers complete digital document solutions for healthcare organisations, streamlining processes, efficient transactions, and cost-effective services.

Learn More
eSignatures Healthcare Industry

Accountancy & Tax

Digital solutions for accountancy and tax, e-signatures for HMRC documents, book keeping and integrations into leading softwares.

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eSignatures Accountancy Industry

Legal

Streamline document turnaround and completion, increase compliance and elevate contract reviews with a digital document management solution.

Learn More
eSignatures Legal Industry

Education

eSign offers digital solutions for educational organisations, from student enrolment, financial aid documents, HR documents and more.

Learn More
eSignatures Education Industry

Finance

Digitise key financial agreements and workflows, do business faster and eliminate slow manual processes with an electronic signature.

Learn More
eSignatures Finance Industry

Discover more industries

eSign provides digital solutions for organisations and individuals across all industries.

Learn More
Discover More Industries

Frequently Asked Questions

An Application Programming Interface, or API, is a software intermediary that allows multiple applications to communicate with each other. An API connects your business processes, services, content, and data to channel partners, internal teams, and independent developers in an easy and secure way.

An API provides customers with an assortment of well-integrated features, providing greater flexibility and convenience that’s ideal when using digital signatures alongside other applications.

The E-Sign API enables developers to seamlessly incorporate E-Sign’s electronic signature features into their own applications. By utilising this API, developers gain the ability to effortlessly create, send, and oversee documents that necessitate electronic signatures. Furthermore, the API facilitates the tracking of document signing progress and provides the means to manage account settings and users.

The E-Sign API offers a fantastic solution for streamlining the management of signed agreements. Developers can effortlessly integrate their systems with the E-Sign API, which provides a dependable and user-friendly method to upload documents, initiate signing requests, send reminders, and gather e-signatures.

Here you will find some of the key definitions of words used throughout our API.

Document

Documents are the files uploaded to E-Sign that form part of an envelope. Once a file has been uploaded it can be used to create templates, be sent as part of an envelope, or be added as an attachment to an envelope.

Envelope

Envelopes are structures that contain data required for a successful E-Signature transaction. Each envelope contains one or more documents, signers, and meta data such as the envelope author and transaction information. Envelopes have unique IDs that can be referenced to interact with the envelope.

Signer

Signers refer to the primary recipients of envelopes. They are specified during the creation of an envelope, and they are directed to view, agree, and sign envelopes. Each envelope must have one or more signers.

Template

Templates are reusable blueprints that can be used to quickly send out envelopes using common information. Frequently used documents or signer groups can be set up easily.

Webhook

Webhooks are automated messages sent from apps when something happens. They have a message—or payload—and are sent to a unique URL. Webhooks are almost always faster than polling and require less work on your end.

OAuth

Use OAuth to securely get access to your users’ data without them sharing their E-Sign password.

OAuth, or open authorisation, is a widely adopted authorisation framework that allows you to consent to an application interacting with another on your behalf without having to reveal your password. It does this by providing access tokens to third-party services without exposing user credentials.

To use our API, you will require an api key, separate keys may be required to access the sandbox environment. API keys do not expire unless you revoke them. Requests are authenticated using the ‘Authorisation: Token API_KEY’ header.

Example:

curl -X GET “https://sandbox.e-sign.co.uk/v3/accounts” -H “accept: application/json” -H “Authorisation: Token API_KEY”

E-Sign uses conventional HTTP response codes to indicate the success or failure of an API request. In general: Codes in the 2xx range indicate success. Codes in the 4xx range indicate an error that failed given the information provided (e.g., a required parameter was omitted, a charge failed, etc.). Codes in the 5xx range indicate an error with E-Sign’s servers (these are rare).

Code Explanation
200 – OK Everything worked as expected.
201 – Created The request succeeded, and a new resource was created as a result.
204 – No Content The server has successfully fulfilled the request and that there is no additional content to send in the response payload body.
400 – Bad Access The request was unacceptable, often due to missing a required parameter.
401 – Unauthorised No valid API key provided.
402 – Request Failed The parameters were valid but the request failed.
403 – Forbidden The API key doesn’t have permissions to perform the request.
404 – Not Found The server can not find the requested resource – the endpoint is valid but the resource itself does not exist.
409 – Conflict The request conflicts with another request (perhaps due to using the same idempotent key).
410 – Gone This response is sent when the requested content has been permanently deleted from the server, with no forwarding address.
422 – Unprocessable Entity The request was well-formed but was unable to be followed due to semantic errors.
429 – Too Many Requests Too many requests hit the API too quickly. We recommend an exponential backoff of your requests.
500, 502, 503, 504 – Server Errors Something went wrong on E-Sign’s end. These responses are very uncommon.

Our API lets you customise and extend the functionality of your apps to meet your unique business needs. Create efficiencies with our API, guided by our comprehensive developer documentation guides and code samples.

To access our API, the first step is to request an API token. Once you have the access token, you can test access to our API through our API Reference. The API Reference makes interacting with our API easy and intuitive.

Learn more about getting started with our API in our guide.

To upload a document through E-Sign’s API you will need:

  • The document title – E.g New Contract
  • BASE64 encoded document
  • Extension – Options: pdf, doc, docx, rtf, txt, ppt, png, jpg
  • File type – Options: document, attachment, logo, email_signature, avatar, seal

You will need to make a POST request to the endpoint https://${ENV}.e-sign.co.uk/v3/uploads, providing the parameters mentioned above.

Visit the full guide for uploading a document.

To create an envelope in its simplest form, certain minimum parameters must be included in the body of the request. These include providing a title for your envelope, specifying the title and ID of the document to be added, and the name and email of the signer.

It is important to note that you need to upload the document to our system before adding it to the envelope. See the ‘How to Upload a File’ guide in our Developer Hub if you’re unsure how to do this. 

Visit the full guide to see how to generate your envelope.

To sign a document within an envelope, you will need the following information: the ID of the signer (signer_id) and the ID of the document (document_id) that is to be signed.

To sign a document, make a POST request to the following endpoint, including the signer_id and document_id:

POST https://${ENV}.e-sign.co.uk/v3/signers/${SIGNER_ID}/documents/${DOCUMENT_ID}

Replace ${SIGNER_ID} and ${DOCUMENT_ID} with the appropriate IDs of the signer and document, respectively.

Visit the full guide to learn how to sign a document.

The “Adding Fields to a Document Using an Iframe” feature allows you to embed an iframe within your application, giving you access to our web application. This enables you to add fields to your document and send your envelope without developing a custom interface.

Visit the full guide to learn more about adding fields to your document.

Did you know that you can track and receive updates on the status of an envelope once it has been created, completed, signed, or declined? By setting up webhooks, you can monitor these events in real time.

Our webhooks guide will take you through the process of creating, viewing, and deleting webhooks using E-Sign’s API.

The “One Click Send and Sign” feature allows users to view a document, enter their information, click a single button to sign, and complete the process—all in just one click.

Visit our full Click to Sign guide in the Developer Hub.

OAuth2 is a robust and flexible authorisation framework that allows users to grant third-party applications limited access to their resources on the E-Sign platform without exposing their credentials.

By using the authorisation code grant flow, OAuth2 enables secure, delegated access where users can authorise an application to act on their behalf, ensuring that the application only accesses what is necessary and within the permissions granted.

Learn everything you need to know about using OAuth, including creating an OAuth app and requesting user authorisation, in our guide.

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