> ## Documentation Index > Fetch the complete documentation index at: https://docs.voltview.co.uk/llms.txt > Use this file to discover all available pages before exploring further. # Submit meter reading to supplier > Submit a meter reading to the supplier (Octopus Energy, E.ON Next, British Gas Lite). The reading is saved to Firestore with status PENDING first, then sent to the supplier; the document is updated to SUCCESS or FAILED. Supports single-register (gas or single-rate electricity), day/night (2 registers), or multi-register (e.g. green/amber/red). Get registerIds from the supplier account's meter details (e.g. from account sites). On failure, the response includes readingId so you can retry within the typical 10-day submission window. ## OpenAPI ````yaml /api-reference/openapi.json post /v1/suppliers/accounts/{id}/readings openapi: 3.0.3 info: title: VoltView API description: >- The VoltView API provides comprehensive energy monitoring and management capabilities for multi-site businesses, enabling real-time tracking of energy consumption, cost analysis, and environmental impact metrics. Our API suite includes: - Site Management API - Manage and monitor multiple site locations - Energy Consumption API - Access detailed energy usage data - Cost Analysis API - Track and analyse energy costs - Environmental Metrics API - Monitor carbon emissions and energy efficiency - Bill Validation API - Validate and audit utility bills for accuracy - Supplier Integration API - Integrate with utility suppliers for automated data collection ## Getting started guide To start using the VoltView API, you need to: - Sign up for a VoltView account to receive your API credentials - Review our data granularity options (hourly/daily/monthly) - Ensure your requests are sent via HTTPS - All responses are returned in JSON format ## Authentication Include your VoltView API key in the `x-api-key` header on every request. ### Authentication error response If authentication fails, you will receive an HTTP 401 Unauthorised response with a detailed error message in the JSON response body. ## Data Units - Energy Consumption: kWh - Power Demand: kW - Carbon Emissions: kg CO2e/tonnes CO2e - Currency: GBP (£) - Time Series: ISO 8601 format - Numeric Values: Rounded to 2 decimal places version: 1.0.0 contact: email: info@voltview.co.uk license: name: Proprietary servers: - url: https://api.voltview.co.uk description: Production server security: - apiKeyAuth: [] tags: - name: Authentication description: Endpoints for authentication - name: User description: User profile management - name: Sites description: Multi-site management endpoints - name: Energy Consumption description: Energy consumption data endpoints - name: Specific Site description: Operations for specific sites - name: Meters description: Meter lookup and meter readings management - name: Emissions description: Carbon emissions data endpoints - name: LOA Management description: >- Letter of Authority (LOA) management - create, list, view, and update status of LOAs - name: Supplier Integration description: Utilities integration endpoints - name: Billing Insights description: Account-level billing insights and bill assurance opportunities - name: Bill Validation description: Utility bill validation and error detection endpoints paths: /v1/suppliers/accounts/{id}/readings: post: tags: - Supplier Integration summary: Submit meter reading to supplier description: >- Submit a meter reading to the supplier (Octopus Energy, E.ON Next, British Gas Lite). The reading is saved to Firestore with status PENDING first, then sent to the supplier; the document is updated to SUCCESS or FAILED. Supports single-register (gas or single-rate electricity), day/night (2 registers), or multi-register (e.g. green/amber/red). Get registerIds from the supplier account's meter details (e.g. from account sites). On failure, the response includes readingId so you can retry within the typical 10-day submission window. operationId: submitMeterReadingToSupplier parameters: - in: path name: id required: true schema: type: string description: Supplier account ID requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/SubmitMeterReadingToSupplierRequest' examples: single: summary: Single read (gas or single-rate electricity) value: mpanMprn: '1234567890123' readAt: '2026-03-15' readings: - registerId: reg-abc-001 reading: 45231 dayNight: summary: Day/night (two registers) value: mpanMprn: '1234567890123' readAt: '2026-03-15' readings: - registerId: reg-night-001 reading: 12000 - registerId: reg-day-002 reading: 28500 multiRegister: summary: Green/amber/red (multi-register) value: mpanMprn: '1234567890123' readAt: '2026-03-15' readings: - registerId: reg-green-001 reading: 5000 - registerId: reg-amber-002 reading: 15000 - registerId: reg-red-003 reading: 22000 responses: '200': description: Meter reading submitted successfully to supplier content: application/json: schema: type: object properties: success: type: boolean example: true message: type: string readingId: type: string description: Unique id for this submission (for retries) data: type: object description: Supplier API response warning: type: string description: Optional e.g. readAt older than 10 days '400': description: Bad request - invalid body, meter not found, or supplier rejected content: application/json: schema: type: object properties: success: type: boolean example: false message: type: string readingId: type: string description: Reading saved to Firestore; retry within submission window error: type: string warning: type: string '500': description: Failed to save reading to Firestore content: application/json: schema: type: object properties: success: type: boolean example: false message: type: string readingId: type: string 4XX: $ref: '#/components/responses/Error4XX' components: schemas: SubmitMeterReadingToSupplierRequest: type: object required: - mpanMprn - readAt - readings properties: mpanMprn: type: string description: MPAN (electricity) or MPRN (gas) for the meter readAt: type: string description: Date of the reading (ISO 8601 date e.g. 2026-03-15) readings: type: array minItems: 1 description: >- One or more register readings. Get registerIds from the supplier account's meter details. items: type: object required: - registerId - reading properties: registerId: type: string description: Register ID from supplier meter details reading: type: number minimum: 0 description: Cumulative register value (non-negative integer) responses: Error4XX: description: Client error response content: application/json: schema: type: object properties: type: type: string enum: - error error: type: object properties: type: type: string enum: - invalid_request_error message: type: string default: Invalid request securitySchemes: apiKeyAuth: type: apiKey in: header name: x-api-key description: VoltView API key ````