> ## Documentation Index
> Fetch the complete documentation index at: https://docs.wirexapp.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Unified Balance

How WUSD and WEUR unified stablecoins power chain-agnostic balance management in Wirex BaaS.

## Before You Start

Read the following guides before proceeding:

| Guide                                  | Why                                        |
| -------------------------------------- | ------------------------------------------ |
| [Getting Started](https://docs.wirexapp.com/docs/getting-started) | Platform overview and setup                |
| [Api Basics](https://docs.wirexapp.com/docs/api-basics)           | Required headers and request configuration |
| [Authentication](https://docs.wirexapp.com/docs/authentication)   | How to obtain access tokens                |
| [Onboarding](https://docs.wirexapp.com/docs/dev-onboarding)       | User and wallet registration               |
| [ABI Reference](https://docs.wirexapp.com/docs/abi-reference)     | Smart contract ABIs                        |

***

## Overview

The Unified Balance represents a user's stable value across all operations in Wirex BaaS. Instead of holding multiple versions of USDT, USDC, or EURC across different blockchains, Wirex normalizes all stable value into:

* **WUSD** — Unified USD, for USD-equivalent value
* **WEUR** — Unified EUR, for EUR-equivalent value

These unified tokens exist on Base chain and provide a chain-agnostic, asset-agnostic model for all internal balances, transfers, and settlements.

> **Note:** Cross-chain deposits via Smart Deposit Addresses are covered in [Global Addresses](https://docs.wirexapp.com/docs/global-addresses). This document focuses on unified stablecoin mechanics.

***

## Why WUSD and WEUR Exist

External stablecoins vary widely:

* Different token standards (ERC-20, TRC-20, SPL, KIP)
* Different decimal precision
* Chain-specific semantics and gas rules
* Inconsistent liquidity conditions
* Various settlement and finality models

This fragmentation makes unified accounting complex. WUSD and WEUR solve these issues by acting as canonical internal stablecoins for all accounting, settlement, and value transfers.

| Problem                   | Solution                          |
| ------------------------- | --------------------------------- |
| Different token standards | Single canonical unified asset    |
| Multi-chain fragmentation | One currency ledger               |
| Complex reconciliation    | Single accounting source of truth |
| Conversion inconsistency  | Always 1:1 ratio                  |
| Bridge logic complexity   | Never needed internally           |
| Liquidity fragmentation   | Unified global pool               |

***

## How Unified Tokens Are Created

### Deposit Minting (Wrap)

When users deposit external stablecoins (USDC, USDT, EURC) to their Smart Wallet:

1. Deposit received on source blockchain
2. Transaction verified
3. Equivalent WUSD or WEUR minted at 1:1 ratio
4. User's Unified Balance credited

Original tokens are held in reserve while unified tokens represent the internal value.

### Direct Credit Minting

Certain operations create WUSD/WEUR directly:

* **Card refunds** — Merchant refund credits
* **Bank transfers** — Incoming fiat via SEPA/ACH
* **Internal transfers** — Peer-to-peer within Wirex
* **Rewards** — Cashback and promotional credits

These mint unified tokens directly, maintaining 1:1 backing through Wirex reserve management.

### Minting Flow

```
On-Chain Deposits              Off-Chain Credits
 USDC, USDT, EURC               Card Refund, Bank Transfer
        ↓                               ↓
   Wrap (1:1)                    Direct Mint (Fiat-backed)
        ↓                               ↓
        └───────────────────────────────┘
                        ↓
              Smart Wallet (WUSD / WEUR)
                  Unified Balance
```

### Minting Properties

| Property          | Description                               |
| ----------------- | ----------------------------------------- |
| Minting ratio     | Always 1:1 with source value              |
| Decimal precision | 18 decimals (WUSD/WEUR)                   |
| Backing           | Fully reserved (deposits + fiat reserves) |
| Reversibility     | Can be unwrapped back to base tokens      |
| Transferability   | Internal transfers within Wirex ecosystem |

***

## Unwrap Mechanics (Withdrawals)

When sending value to an external blockchain address, unified assets are unwrapped into external stablecoins.

### Unwrap Flow

```mermaid
sequenceDiagram
    participant User
    participant App
    participant Wallet as Smart Wallet
    participant Policy as Delay Policy
    participant Tokens

    Note over User,Tokens: Phase 1: Request
    User->>App: Initiate transfer
    App->>Wallet: Encode unwrap + transfer calls
    Wallet->>Policy: Create request()
    Policy-->>Wallet: Store with delay
    App-->>User: Request initiated

    Note over User,Tokens: DELAY PERIOD

    Note over User,Tokens: Phase 2: Execute
    User->>App: Execute transfer
    App->>Wallet: Send with nonce
    Wallet->>Policy: Verify delay passed
    Policy-->>Wallet: Approved
    Wallet->>Tokens: Burn WUSD, release USDC
    Wallet->>Tokens: Transfer to recipient
    App-->>User: Transfer completed
```

### Supported Unwrap Paths

| Unified | Result Token | Chain |
| ------- | ------------ | ----- |
| WUSD    | USDC         | Base  |
| WEUR    | EURC         | Base  |

***

## Token Addresses

### Production (Base Mainnet - Chain ID 8453)

| Token | Address                                      | Decimals |
| ----- | -------------------------------------------- | -------- |
| USDC  | `0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913` | 6        |
| USDT  | `0xfde4C96c8593536E31F229EA8f37b2ADa2699bb2` | 6        |
| EURC  | `0x60a3E35Cc302bFA44Cb288Bc5a4F316Fdb1adb42` | 6        |
| WUSD  | `0xb4bB2032A73A53C0Aa7Dc9ee2d9658a978fA7bC2` | 18       |
| WEUR  | `0x379e120C1921bFD8f5E0A1a3C699e7e800b66606` | 18       |

### Sandbox (Base Sepolia - Chain ID 84532)

| Token | Address                                      | Decimals |
| ----- | -------------------------------------------- | -------- |
| USDC  | `0x7Af7cDbd557eD302F7538Db1e3d094C8BBcA665c` | 6        |
| USDT  | `0x2C6c7c00ACa9B9D8446d107367485079b0471706` | 18       |
| EURC  | `0xF70461ffb413981852683657A310892227e3989e` | 6        |
| WUSD  | `0x0774164DC20524Bb239b39D1DC42573C3E4C6976` | 18       |
| WEUR  | `0x5c55F314624718019A326F16a62A05D6C6d8C8A2` | 18       |

***

## Retrieving Unified Balance

```
GET /api/v1/wallet
```

**Response (balances excerpt):**

```json
{
  "balances": [
    {
      "token_symbol": "WEUR",
      "token_address": "0x5f0818Cfc6554aC3d018aeF81D310ABC1dcCcCD7",
      "balance": 7.27,
      "reference_balance": 8.40,
      "reference_currency": "USD"
    },
    {
      "token_symbol": "WUSD",
      "token_address": "0xD08C1401dd0E8aA012D9C7b4471d45FdC8f1C97E",
      "balance": 1581.07,
      "reference_balance": 1581.07,
      "reference_currency": "USD"
    }
  ]
}
```

| Field                | Description                       |
| -------------------- | --------------------------------- |
| `token_symbol`       | WUSD or WEUR                      |
| `token_address`      | Unified token contract on Base    |
| `balance`            | Amount in unified token           |
| `reference_balance`  | Converted to reference currency   |
| `reference_currency` | Reference currency (default: USD) |

***

## Summary

WUSD and WEUR are the foundational unified stablecoins powering all Unified Balance mechanics in Wirex BaaS:

* Single canonical asset per currency
* Deterministic internal accounting
* Unified global liquidity
* Chain-agnostic operations
* Seamless unwrap → blockchain send workflows
* No developer management of token formats or bridging

By integrating with Unified Balance, developers gain a simple, reliable way to handle stablecoin value across any chain.