> ## Documentation Index > Fetch the complete documentation index at: https://docs.polygon.technology/llms.txt > Use this file to discover all available pages before exploring further. # Get customer balance > Get the aggregated estimated balance across all customer wallets/assets. ## OpenAPI ````yaml /api-reference/openapi.yaml get /customers/{id}/balance openapi: 3.0.3 info: title: Polygon OMS Public API version: v26.05.28-0001 description: >- Unified API for moving money between crypto and fiat. Three ways to move money: Transactions (instant, wallet or card funded, including Cash-In for in-person cash deposits), Deposit Addresses (reusable crypto deposit configurations), and Virtual Accounts (dedicated bank accounts that auto-convert fiat to crypto). Standard transactions follow a two-step flow: create a Quote (pricing), then create a Transaction (execution). Cash-in codes generate a one-time deposit code for in-person cash deposits at retail locations. contact: name: Polygon OMS url: https://oms.polygon.technology servers: - url: https://sandbox-api.polygon.technology/v0.13 description: Sandbox - url: https://api.polygon.technology/v0.13 description: Production security: - BearerAuth: [] tags: - name: Auth description: Authentication via FrontEgg - name: Customers description: Customer management and KYC - name: Customer - name: Wallet - name: Quote - name: Transaction - name: CashIns - name: CashLocation - name: Sandbox - name: VirtualAccount - name: Counterparty - name: ExternalAccount - name: Reference - name: DepositAddress paths: /customers/{id}/balance: get: tags: - Customer summary: Get customer balance description: Get the aggregated estimated balance across all customer wallets/assets. operationId: getCustomerBalance parameters: - name: id in: path required: true description: Customer ID (`cst_` prefix). schema: type: string - name: estimatedBalanceCurrencyCode in: query required: false description: ISO 4217 currency for the estimated value. Defaults to USD. schema: type: string responses: '200': description: The request has succeeded. content: application/json: schema: $ref: '#/components/schemas/CustomerBalanceAggregate' '400': description: The server could not understand the request due to invalid syntax. content: application/json: schema: $ref: '#/components/schemas/InvalidCustomerIdErrorBody' '401': description: Access is unauthorized. content: application/json: schema: $ref: '#/components/schemas/UnauthorizedErrorBody' '404': description: The server cannot find the requested resource. content: application/json: schema: $ref: '#/components/schemas/CustomerNotFoundErrorBody' '422': description: Client error content: application/json: schema: $ref: '#/components/schemas/ProviderUserAccountNotFoundErrorBody' '502': description: Server error content: application/json: schema: $ref: '#/components/schemas/ProviderErrorBody' '503': description: Service unavailable. content: application/json: schema: $ref: '#/components/schemas/ProviderUnreachableErrorBody' components: schemas: CustomerBalanceAggregate: type: object required: - data properties: data: type: object properties: customerId: allOf: - $ref: '#/components/schemas/typeId' description: Public OMS customer ID, format `cst_`. estimatedBalanceValue: allOf: - $ref: '#/components/schemas/fixedDecimalString' description: >- Estimated total balance value across all customer wallets/assets, in the currency requested via the `estimatedBalanceCurrencyCode` query param. Defaults to USD when the query param is omitted. Decimal string. estimatedBalanceCurrencyCode: type: string description: Currency code used for `estimatedBalanceValue`. updatedAt: type: string format: date-time description: >- Most recent provider balance timestamp included in the aggregate. Omitted when no provider balance timestamps were available to aggregate. totalBalance: allOf: - $ref: '#/components/schemas/CustomerTotalBalance' description: |- USD balance rollup (fiat / crypto / total) for OMSX to compose `Customer.totalBalance` (v0.11-8, #2362). Mirrors the OMS `Customer.totalBalance` shape 1:1. Omitted as a whole when the Coinme provider read (or the fiat mirror read) fails — a partial/half total is never returned. `estimatedBalanceValue` above is retained unchanged for back-compat. required: - customerId - estimatedBalanceValue - estimatedBalanceCurrencyCode description: >- A customer's estimated total balance, aggregated across all of their wallets and assets. InvalidCustomerIdErrorBody: type: object required: - error properties: error: type: string enum: - invalid customer id description: Human-readable error identifier. UnauthorizedErrorBody: type: object required: - error properties: error: type: string enum: - unauthorized description: Human-readable error identifier. CustomerNotFoundErrorBody: type: object required: - error properties: error: type: string enum: - customer not found description: Human-readable error identifier. ProviderUserAccountNotFoundErrorBody: type: object required: - error - code properties: error: type: string enum: - provider account not provisioned for this customer description: Human-readable error identifier. code: type: string enum: - providerUserAccountNotFound description: Machine-readable code. ProviderErrorBody: type: object required: - error - code properties: error: type: string description: Human-readable error identifier. code: type: string enum: - providerError description: Machine-readable code. ProviderUnreachableErrorBody: type: object required: - error - code properties: error: type: string enum: - upstream provider unreachable description: Human-readable error identifier. code: type: string enum: - providerUnreachable description: Machine-readable code. typeId: type: string pattern: >- ^[a-z]+_([0-9a-hjkmnp-tv-z]{26}|[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12})$ description: >- Public TypeID, e.g. `txn_01h455vb4pex5vsknk084sn02q`; legacy UUID suffixes are accepted until non-v7 rows are retired. x-go-type: string fixedDecimalString: type: string description: Wire-safe decimal string that preserves trailing zeros on the wire. x-go-type-import: path: github.com/0xPolygon/bpn-lib/numeric x-go-type: numeric.FixedDecimalString CustomerTotalBalance: type: object properties: totalUsd: allOf: - $ref: '#/components/schemas/signedFixedDecimalString' description: |- `fiatUsd + cryptoUsd`, formatted to 2 decimal places, sign preserved (e.g. `"25.00"`, `"-15.50"`). fiatUsd: allOf: - $ref: '#/components/schemas/signedFixedDecimalString' description: |- Signed sum of the customer's USD fiat-wallet balances, read from the cached Erebor mirror (`account_balances`, USD 1:1). No Erebor call on the hot path. Formatted to 2 decimal places, sign preserved. cryptoUsd: allOf: - $ref: '#/components/schemas/signedFixedDecimalString' description: >- Signed sum of Coinme custodial crypto balances valued in USD, formatted to 2 decimal places. `"0.00"` for a customer with no Coinme account. description: >- USD balance rollup exposed on the customer-balance read, shaped to match the OMS `Customer.totalBalance` object so OMSX maps it field-for-field. All three values are signed USD decimal strings (a fiat balance may be negative after an ACH clawback that overdraws the deposit account, so the total may be negative too — consumers must render the sign verbatim, never clamp to zero). Read-only: this object appears only on the balance GET. `cryptoUsd` is custodial-only. It sums Coinme's per-asset `estimatedBalanceValue` (already USD-denominated; no new oracle/pricing). Embedded (non-custodial) wallets have no balance source in BPN and are not valued here. An Erebor-only customer (no Coinme account) gets `cryptoUsd = "0"` rather than a 422. signedFixedDecimalString: type: string description: >- Wire-safe decimal string for signed financial values that must ship with a fixed scale (trailing zeros preserved). It combines the two guarantees the OMS `Customer.totalBalance` fields need at once: the leading minus is part of the contract — a fiat balance may be negative after an ACH clawback, so consumers render the sign as-is and never clamp to zero — and the scale is preserved on the wire (e.g. `"25.00"`, `"-25.00"`, `"0.00"`), unlike `signedDecimalString`/`decimal.Decimal`, whose `.String()` trims trailing zeros (`"25.00"` → `"25"`). Same underlying `numeric.FixedDecimalString` Go type as `fixedDecimalString`; the builder is responsible for setting the scale (via `StringFixed`). x-go-type-import: path: github.com/0xPolygon/bpn-lib/numeric x-go-type: numeric.FixedDecimalString securitySchemes: BearerAuth: type: http scheme: bearer bearerFormat: JWT description: Token from POST /auth/token ````