Polygon ID: How to Check Its Identity Privacy

Polygon ID is identity technology, not a guarantee that your personal data is safe. It was designed to let people prove claims about themselves using verifiable credentials and zero-knowledge proofs. For example, a service might check that you meet an eligibility rule without asking to see every detail on an identity document.

The important distinction is that a proof can limit what you disclose, but it cannot make every part of an identity check private automatically. The credential issuer, the app asking you to prove something, your wallet and any network transactions all affect what information is exposed.

The name has also changed. Polygon ID became Privado ID in 2024; reporting in 2025 described the project as rebranded Billions. If you encounter “Polygon ID” in an older guide or app, check who operates the current product and whether it is the service you intended to use.

Treat the privacy claim as a feature to verify, not a security guarantee. Before connecting a wallet or presenting a credential, find out what is requested, who can see it and how you can revoke access or credentials.

The basic model has three roles. An issuer creates a credential, such as a claim that an account meets a particular requirement. You hold that credential in a compatible wallet or identity app. A verifier—such as a website or service—asks you to prove a specific claim.

A verifiable credential is not necessarily a government-issued ID. Its value depends on who issued it, what they checked and whether the verifier trusts that issuer. A credential can be technically valid while the original claim is inaccurate, outdated or unsuitable for the decision being made.

With a zero-knowledge proof, you may be able to prove a fact without revealing the full credential. Instead of sending a complete document, an implementation could let you prove that a condition is true. What you can prove, and which details remain hidden, depends on how the issuer and app have built the system.

That makes the system different from uploading a scan of your passport, but it does not remove the need to assess the service. Ask who issued the credential, what exact claim is being checked, whether the credential expires and whether the verifier receives information that could identify or track you.

Zero-knowledge proofs can reduce disclosure, but “zero knowledge” does not mean “no one learns anything.” A verifier may learn the answer to the question it asked—for example, whether you qualify—even if it does not receive the underlying document. The issuer may already know your identity because it checked your information when issuing the credential.

The interaction can also create other data. A service may associate a proof with your account, device or activity. A public blockchain can expose transaction details if an implementation records them there. Even when personal details are not placed on-chain, addresses and timing can sometimes be linked to other activity.

Before approving a request, check:

• The exact attributes or claims the app wants you to prove.
• Whether it asks for a full credential or only a limited proof.
• Who issued the credential and who will receive the result.
• Whether the app explains data retention, revocation and expiry.
• Whether a transaction is required, and what it will publish.

If the prompt is vague, asks for unrelated details or differs from the service’s explanation, decline and contact the service through a channel you independently trust.

A name change can make it harder to tell whether an app is current, official or simply using old terminology. Polygon ID became Privado ID in 2024, and reporting in 2025 described a later rebrand to Billions. That history does not, by itself, establish that every app using the earlier name is connected to the current project.

Before installing an identity app or connecting a wallet, confirm the developer’s identity from a trusted, independently verified channel. Check the app’s publisher, current documentation, requested permissions and privacy policy. Be cautious of sponsored search listings, unsolicited messages and social posts that ask you to import a wallet or reveal a recovery phrase.

Use this quick check:

1. Confirm the product name and developer match the service you meant to use.
2. Check whether the app is maintained and whether its permissions fit its purpose.
3. Look for an explanation of credential storage, sharing and revocation.
4. Confirm the issuer of any credential before relying on its claims.
5. Stop if an app asks you to enter a wallet recovery phrase to verify your identity.

An identity credential and a wallet recovery phrase are not interchangeable. A legitimate identity check should not require you to surrender control of your crypto wallet.

There is no single Polygon ID consumer fee that applies to every identity check. The cost depends on the app and how it issues, stores or verifies credentials. Some flows may not require you to pay a network fee directly; others may involve a blockchain transaction or a service charge. Check the specific app’s terms and the wallet’s transaction preview before proceeding.

Do not assume a credential is free just because creating a proof is described as private or simple. Look for any fee before you begin, and confirm who receives it. If a wallet asks you to approve a transaction, read the network, destination and requested permissions; an identity prompt should not be treated as permission to move assets or grant broad token access.

Also check what happens if you lose access to the app or device. Find out whether credentials can be recovered, reissued or revoked, and whether a backup could expose sensitive information. A recovery method that depends on a secret phrase deserves the same care as a crypto wallet backup.

If the app does not explain its charges, data handling or recovery process, pause rather than guessing. You can ask the service for those details before supplying identity information.

A credential is only as trustworthy as its issuer and the process used to create it. Before relying on one, identify who issued it, what evidence they checked and whether the claim is still current. For an important decision, confirm that the verifier accepts that issuer and credential type; a proof cannot make an untrusted issuer reliable.

Check whether the credential expires or can be revoked. A credential that was valid when issued may no longer reflect your circumstances. If a service uses an outdated or compromised credential, its cryptographic validity alone does not guarantee the underlying claim remains true.

For the app itself, look for clear security documentation and the status of any audits relevant to the software you will use. An audit of one component does not automatically cover the wallet, issuer, verifier or later versions. Open-source code can help qualified reviewers inspect a project, but publication alone is not proof that code is safe or that a deployed app matches it.

Do not share more than the service needs. If an app asks you to disclose a full identity document when a narrower proof would meet the purpose, ask why. If you cannot get a clear answer, consider whether the service is worth using.

A safer identity flow starts with the service asking for a limited, understandable claim. You should be able to see which credential or attribute it wants, who will verify it and whether the result is recorded. If the request is unexpected, stop before connecting a wallet or presenting a credential.

Use these safeguards:

• Install identity software only from a developer channel you have verified.
• Keep your device and wallet software up to date.
• Never enter a recovery phrase into a website, identity form or support chat.
• Review each wallet prompt; reject transactions or permissions unrelated to the check.
• Avoid reusing public wallet addresses across services when that could link your activity.
• Keep a secure backup of credentials only if the app explains how that backup is protected.
• Ask how to revoke a credential or delete account data when you no longer need the service.

A credential may be personal information even if it is not a passport scan. Protect access to it, and be wary of messages claiming you must act urgently to preserve or verify your identity. If you suspect an account or credential has been exposed, contact the issuer and service through verified channels and follow their revocation and recovery steps.

The biggest mistake is treating zero-knowledge proofs as a blanket privacy shield. They can reduce what a verifier learns, but the specific app still determines what is requested, stored and linked. Read the prompt rather than relying on a feature label.

Other mistakes to avoid:

• Trusting the name alone: Polygon ID, Privado ID and Billions refer to a changing project identity. Verify the current developer behind the app.
• Trusting any credential equally: Check the issuer and how the claim was verified.
• Approving without reading: A wallet request may authorize an unrelated transaction or permission.
• Sharing a recovery phrase: No identity verification should require your wallet’s secret recovery phrase.
• Ignoring revocation and expiry: Ask how a credential can be invalidated and whether it remains current.
• Assuming no data is stored: Ask the service what it retains, for how long and who can access it.

Polygon ID’s approach can support more selective identity checks than sending a full document, but the outcome depends on the implementation. Use it only when the issuer, app, requested proof and data-handling practices make sense to you. If you cannot establish those basics, do not present the credential.