Lawmatics Payment Invoices API
The Payment Invoices API from Lawmatics — 2 operation(s) for payment invoices.
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OpenAPI Specification
openapi: 3.2.0
info:
title: Lawmatics OAuth Payment Invoices API
version: 1.22.0
description: 'The official Lawmatics REST API for legal CRM, client intake and law firm automation. Manage matters (prospects), contacts, companies, custom forms and form entries, custom fields, events and appointments, tasks, notes, files, tags, users, time entries, expenses, invoices and transactions.
Authentication is OAuth 2.0 authorization code grant; access tokens do not expire, there are no refresh tokens, and Lawmatics does not currently support scopes - an authorized app receives full CRUD access to the granted account.
All list endpoints support the shared query-parameter grammar documented in the Param Guide: `fields` (field selection, one level deep, `fields=all` to expand), `page` (pagination), `sort_by`/`sort_order`, and `filter_by`/`filter_on`/`filter_with` (one filter at a time; operators `=`, `!=`, `<=`, `<`, `>=`, `>`, `like`, `ilike`, `null`, `not_null`).
Responses follow a JSON:API-style `data` / `attributes` / `relationships` envelope.'
contact:
name: Lawmatics API Support
email: api@lawmatics.com
url: https://docs.lawmatics.com/
termsOfService: https://www.lawmatics.com/terms-of-use
servers:
- url: https://api.lawmatics.com
description: Lawmatics production API
security:
- oauth2: []
- bearerAuth: []
tags:
- name: Payment Invoices
paths:
/v1/invoices/{invoice_id}:
get:
operationId: getInvoice
summary: Invoice
description: A specific Invoice in Lawmatics
tags:
- Payment Invoices
parameters:
- name: invoice_id
in: path
required: true
description: The invoice id
schema:
type: string
responses:
'200':
description: OK
content:
application/json:
schema:
type: object
examples:
getInvoice:
summary: GET Invoice
value:
data:
id: '1'
type: invoice
attributes:
number: 1
status: sent
target_account_type: operating
payment_terms: due_date
include_balance_forward: false
enable_online_payment: false
include_statement_of_accounts: false
invoiced_at: '2021-11-02'
due_at: '2021-11-02'
voided_at: null
contactable_address: null
contactable_name: Roey Tester
note: "hey zsolt this is a specific invoice note\n\nhere \nis\na \nbunch\n\nof (two)\nnewlines"
amount_cents: 0
amount_paid_cents: 0
outstanding_amount_cents: 0
pdf_url: http://localhost:3000/attachments/80623eb43ae0fa961d5a32b8d169fd54a0249de1/store/511432f743969f1e7b9cc636c1a9c7b4ca1a4d5dd902ef0a1ba405ff89f7/Invoice+%231.pdf
created_at: '2021-11-02T10:28:40.535-07:00'
updated_at: '2022-01-10T19:43:47.382-08:00'
relationships:
invoice_type:
data: null
prospect:
data:
id: '101'
type: prospect
created_by:
data:
id: '5'
type: created_by
forwarded_to:
data: null
time_entries:
data:
- id: '8'
type: time_entry
expenses:
data: []
invoice_adjustments:
data: []
transactions:
data: []
forwarded_from:
data: []
'401':
description: Unauthorized - missing or invalid OAuth 2.0 bearer token
'429':
description: Too Many Requests - the per-firm rate limit was exceeded; a Retry-After header is returned
headers:
Retry-After:
description: Seconds to wait before retrying
schema:
type: integer
/v1/invoices:
get:
operationId: getInvoices
summary: Invoices
description: A paginated list of all Invoices in Lawmatics
tags:
- Payment Invoices
responses:
'200':
description: OK
content:
application/json:
schema:
type: object
examples:
getInvoices:
summary: GET Invoices
value:
data:
- id: '1'
type: invoice
attributes:
number: 1
status: sent
target_account_type: operating
payment_terms: due_date
include_balance_forward: false
enable_online_payment: false
include_statement_of_accounts: false
invoiced_at: '2021-11-02'
due_at: '2021-11-02'
voided_at: null
contactable_address: null
contactable_name: Roey Tester
note: "hey zsolt this is a specific invoice note\n\nhere \nis\na \nbunch\n\nof (two)\nnewlines"
amount_cents: 0
amount_paid_cents: 0
outstanding_amount_cents: 0
pdf_url: http://localhost:3000/attachments/80623eb43ae0fa961d5a32b8d169fd54a0249de1/store/511432f743969f1e7b9cc636c1a9c7b4ca1a4d5dd902ef0a1ba405ff89f7/Invoice+%231.pdf
created_at: '2021-11-02T10:28:40.535-07:00'
updated_at: '2022-01-10T19:43:47.382-08:00'
relationships:
invoice_type:
data: null
prospect:
data:
id: '101'
type: prospect
created_by:
data:
id: '5'
type: created_by
forwarded_to:
data: null
time_entries:
data:
- id: '8'
type: time_entry
expenses:
data: []
invoice_adjustments:
data: []
transactions:
data: []
forwarded_from:
data: []
meta:
total_pages: 1
limit_per_page: 25
total_entries: 1
links:
self: /v1/invoices?page=1
'401':
description: Unauthorized - missing or invalid OAuth 2.0 bearer token
'429':
description: Too Many Requests - the per-firm rate limit was exceeded; a Retry-After header is returned
headers:
Retry-After:
description: Seconds to wait before retrying
schema:
type: integer
components:
securitySchemes:
oauth2:
type: oauth2
description: OAuth 2.0 authorization code grant. Register a developer app at https://app.lawmatics.com/settings/developers (developer settings must be enabled by Lawmatics support). Access tokens are non-expiring; no refresh tokens are issued and scopes are not supported.
flows:
authorizationCode:
authorizationUrl: https://app.lawmatics.com/oauth/authorize
tokenUrl: https://api.lawmatics.com/oauth/token
scopes: {}
bearerAuth:
type: http
scheme: bearer
description: 'The OAuth 2.0 access token is sent as `Authorization: Bearer <access_token>`.'
externalDocs:
description: Official Lawmatics RESTful API documentation (Postman)
url: https://docs.lawmatics.com/
x-provenance:
generated: '2026-08-13'
method: derived
publisher: API Evangelist
source: https://docs.lawmatics.com/api/collections/26379991/2sA3JM7gbw?segregateAuth=true&versionTag=latest
source_type: Postman collection published by Lawmatics as its official API documentation
source_file: postman/lawmatics-oauth-api.postman_collection.json
note: 'NOT published by Lawmatics. Lawmatics publishes no OpenAPI. Every path, method, parameter, request example and response example in this document was converted mechanically from the provider-published Postman collection "Lawmatics OAuth API v1.22.0"; nothing was invented. Schemas are typed as generic objects because the collection carries examples, not JSON Schema. The server URL is the base documented in the collection Param Guide (https://api.lawmatics.com), not the collection''s disabled {{host}} placeholder. The 401 and 429 responses added to every authenticated operation are the provider-documented, globally applicable responses: the collection''s auth guide states a per-firm rate limit applies to all endpoints and returns 429 with a Retry-After header, and https://api.lawmatics.com/v1/contacts was observed returning 401 unauthenticated on 2026-08-13.'