Signing Documents in ‘Diia’: A Complete Guide to Using Ukraine’s E-Signature

Ukraine’s digital transformation has reached a point where the most important documents can be signed without leaving home. The ‘Diia’ portal is already used by millions, but its e-signature function still raises questions. Yet, it is one of the most powerful and secure tools, allowing for the legitimate certification of contracts, applications, and reports. For foreign entrepreneurs exploring the Ukrainian market, understanding Diia is key to efficient operations. We have prepared a detailed guide on how it works.

What is an e-signature in ‘Diia’ and why can it be trusted?

The electronic signature (ES) on the “Diia” portal is not just a graphic image. It is a full-fledged, qualified tool that holds the same legal force as a handwritten signature with a stamp. Its use is enshrined in law, and electronic documents signed with an ES are accepted by all state authorities and can even be used as evidence in court.

Key security feature: when signing, the text of the document is not transmitted to Diia’s servers—the entire encryption and signing process occurs locally, in your browser. This ensures complete data confidentiality.

Step 1: How to sign a document with an e-signature

The process is intuitive and takes just a few minutes. Follow these steps:

1. Upload the key. Go to the relevant section of ‘Diia’ and upload your personal key file (.key or .p12). This key and certificate should be issued to you by one of the accredited service providers.
2. Authorize the key. Select the type of key carrier (file system, token, etc.), enter the container password, and click ‘Read Key’.
3. Upload the document. Drag and drop into the browser window or select the file you need to sign (PDF, DOCX, JPEG, and other formats are supported). Click ‘Continue’.
4. Sign and save. Check the file name and click the ‘Sign File’ button. The system will create a signed copy of the document with the .p7s extension. Saving should happen automatically, but if it doesn’t, do it manually.

Step 2: How to verify the authenticity of an e-signature

Anyone who has a signed file can verify whether the signature is valid and whether the document has been altered after signing.

1. Go to the verification page. On the ‘Diia’ portal, use the special ‘Verify Signature’ link.
2. Upload the signature file. Upload a .p7s format file by dragging it into the browser window or selecting it manually. Click ‘Verify’.
3. Review the result. The system will display detailed information: the signature status (‘Valid’ or ‘Invalid’), the certificate owner’s data, and its validity period.
4. If necessary, you can download the original document or an official verification receipt for your records.

Step 3: Where and how to obtain an e-signature

You cannot sign a document without a qualified certificate. You can obtain one in several ways:

• From accredited providers. These are private companies listed on the ‘Diia’ portal. The process involves submitting an application and providing a passport and tax number. The service is paid.
• For free from state authorities. An e-signature can be obtained from the Information and Reference Department of the State Tax Service, the National Police, or PrivatBank.

Important tips:

• Store the key on a protected removable drive (e.g., a separate flash drive), not on your computer’s hard disk.
• The certificate is valid for 1-2 years. Remember to renew it in time through your provider’s website.

More than a signature: Other possibilities of ‘Diia’

The portal has long outgrown the function of a simple document repository. Today, through ‘Diia’, you can:

• Upload digital copies of important documents: diploma, student ID, birth certificate, making them always accessible.
• Complete a car purchase—the ‘AutoPurchase’ function allows for a safe and transparent transaction.
• Register as unemployed and receive corresponding state services online.

All these and many other services are described in the FAQ section on the official portal.

Digital freedom with a security guarantee

The ability to affix a legally binding signature in a few clicks is not just a convenience; it is a new standard for business and bureaucratic processes. It saves time, eliminates the need for a physical meeting or a trip to another city to sign a contract, and makes business processes more efficient. Thanks to Diia’s architecture, which prevents the document from leaving your browser, this tool is also one of the most secure on the market.

If you haven’t obtained an e-signature yet, now is the perfect time to do so. It is becoming as much of a must-have for entrepreneurs and active citizens as the battery level on a smartphone.