---
title: Multi Accounts
description: Performs a 1:N biometric search against the operator's base to detect whether a face is already linked to another active account.
canonical: https://developer.unico.io/dual-api/capabilities/multi-accounts
locale: en
generated_by: markdown-export
---

Multi Accounts asks "does this face already exist somewhere else in the operator's base?".

:::info[Part of Fraud Risk Classification]
Multi Accounts is a capability of the [Fraud Risk Classification](/capabilities/fraud-risk-classification) product. It is not contracted separately: it is enabled in your API Key configuration during onboarding with Unico.
:::

### What it does

Performs a segmented 1:N biometric search in the operator's base, cross-referencing the received face against all records associated with the same `clientReferenceSegment`. Detects whether the biometric is already linked to a different `clientReference` — indicating that the same person has created, or is attempting to create, multiple accounts with the same operator.

### Inputs

- The user's selfie — in API integrations you send it as `imageBase64` (PNG, JPEG, or WebP; minimum 640×480; maximum 800 KB); in Web integrations the capture is performed by Unico.
- `clientReference` (`subject.clientReference` in API) — **required**. Unique identifier of the user in the operator's system: unique in your base, maximum of 256 characters, no spaces.

### Possible responses

| Response | Meaning |
|---|---|
| `reproved` | Multi-account detected. The facial biometric is already linked to a different `clientReference` within the same segment. |
| `inconclusive` | Multi-account not detected. The face is not registered under any other account in the operator's base. |

This table represents the individual response of the capability.

:::warning[There is no `YES` or `NO` response]
Multi Accounts **does not return `YES` or `NO`** — the absence of duplicity is represented as `inconclusive`, not as a confirmation that there will never be a risk.
:::

### Availability

| Surface | Supported |
|---|:-:|
| **SDK** (Android, iOS, Flutter) | ✅ |
| **Web** (iFrame, Redirect) | ✅ |
| **API** (headless, no SDK) | ✅ |

On every surface the capability requires the user's `clientReference` in the request and enablement in your API Key.

:::tip[API enum values]
In the Web & Native contract response, the Multi Accounts result arrives in the `authenticationInfo.accountFarmingResult` field: `TRUST_RESULT_YES` when a multi-account is detected, `TRUST_RESULT_NO` / `TRUST_RESULT_INCONCLUSIVE` when no duplicity is found. It is a dedicated field — it is not combined with `authenticationInfo.identityFraudstersResult`, which corresponds to a different Fraud Risk Classification evaluation.
:::

:::warning[API integration: liveness]
In API integrations, Liveness is optional. If you send images without a liveness check, the 1:N search runs over an unverified capture (for example, a photo of a photo) and the result inherits that risk. We recommend enabling Liveness in the same process, or capturing with the Unico SDK following the [Capture Standard](/developers/sdks-and-tools/capture-standard).
:::

### Search scope

The search scope is controlled by the `clientReferenceSegment` field, configured by Unico in your API Key during onboarding — it is not a field you send in the request. Distinct segments can coexist within a single operator without triggering false positives (useful for B2B sub-clients or models with personal and business accounts); if your operation needs to segment the search, discuss it with your Unico contact.

### Products that use this capability

- [Multi Accounts](/products/sign-up/multi-accounts)