openapi: 3.2.0 info: title: Lawmatics OAuth Payment Transactions 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 Transactions paths: /v1/transactions/{transaction_id}: get: operationId: getTransaction summary: Transaction description: A specific Transaction in Lawmatics tags: - Payment Transactions parameters: - name: transaction_id in: path required: true description: The transaction id schema: type: string responses: '200': description: OK content: application/json: schema: type: object examples: getTransaction: summary: GET Transaction value: data: id: '1' type: transaction attributes: account_type: Contact bank_account_type: trust status: processed payment_method: venmo transaction_type: credit amount_cents: 12323 amount_currency: USD account_id: 101 created_by_id: 5 firm_id: 2 external_id: null invoice_id: null prospect_id: 101 created_at: '2021-12-26T14:52:44.808-08:00' updated_at: '2021-12-26T14:52:44.808-08:00' note: Such a goo payment relationships: account: data: id: '101' type: contact prospect: data: id: '101' type: prospect invoice: data: null '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/transactions: get: operationId: getTransactions summary: Transactions description: A paginated list of all Transactions in Lawmatics tags: - Payment Transactions parameters: - name: fields in: query required: false schema: type: string example: all responses: '200': description: OK content: application/json: schema: type: object examples: getTransactions: summary: GET Transactions value: data: - id: '6' type: transaction attributes: account_type: Contact bank_account_type: trust status: processed payment_method: other transaction_type: credit amount_cents: 12300 amount_currency: USD account_id: 3 created_by_id: 5 firm_id: 2 external_id: null invoice_id: null prospect_id: null created_at: '2022-04-21T00:17:38.437-07:00' updated_at: '2022-04-21T00:17:38.437-07:00' note: asdasd relationships: account: data: id: '3' type: contact prospect: data: null invoice: data: null - id: '5' type: transaction attributes: account_type: Contact bank_account_type: trust status: processed payment_method: credit_card transaction_type: credit amount_cents: 1230 amount_currency: USD account_id: 3 created_by_id: 5 firm_id: 2 external_id: null invoice_id: null prospect_id: 3 created_at: '2022-04-20T22:37:22.982-07:00' updated_at: '2022-04-20T22:37:22.982-07:00' note: asdasdas relationships: account: data: id: '3' type: contact prospect: data: id: '3' type: prospect invoice: data: null - id: '4' type: transaction attributes: account_type: Contact bank_account_type: trust status: processed payment_method: credit_card transaction_type: credit amount_cents: 1230 amount_currency: USD account_id: 9 created_by_id: 5 firm_id: 2 external_id: null invoice_id: null prospect_id: null created_at: '2022-04-20T16:47:22.562-07:00' updated_at: '2022-04-20T16:47:22.562-07:00' note: asdasdasd relationships: account: data: id: '9' type: contact prospect: data: null invoice: data: null - id: '3' type: transaction attributes: account_type: Contact bank_account_type: trust status: processed payment_method: credit_card transaction_type: credit amount_cents: 12300 amount_currency: USD account_id: 3 created_by_id: 5 firm_id: 2 external_id: null invoice_id: null prospect_id: 3 created_at: '2022-04-20T16:47:07.893-07:00' updated_at: '2022-04-20T16:47:07.893-07:00' note: test relationships: account: data: id: '3' type: contact prospect: data: id: '3' type: prospect invoice: data: null - id: '2' type: transaction attributes: account_type: Contact bank_account_type: trust status: processed payment_method: credit_card transaction_type: credit amount_cents: 123123 amount_currency: USD account_id: 101 created_by_id: 5 firm_id: 2 external_id: null invoice_id: null prospect_id: 101 created_at: '2022-01-10T20:05:03.839-08:00' updated_at: '2022-01-10T20:05:03.839-08:00' note: Tester relationships: account: data: id: '101' type: contact prospect: data: id: '101' type: prospect invoice: data: null - id: '1' type: transaction attributes: account_type: Contact bank_account_type: trust status: processed payment_method: venmo transaction_type: credit amount_cents: 12323 amount_currency: USD account_id: 101 created_by_id: 5 firm_id: 2 external_id: null invoice_id: null prospect_id: 101 created_at: '2021-12-26T14:52:44.808-08:00' updated_at: '2021-12-26T14:52:44.808-08:00' note: Such a goo payment relationships: account: data: id: '101' type: contact prospect: data: id: '101' type: prospect invoice: data: null meta: total_pages: 1 limit_per_page: 25 total_entries: 6 links: self: /v1/transactions?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 post: operationId: createTransaction summary: Create Transaction description: "Create a new Transaction\n\nOptional Fields: invoice_number, invoice_id, note \n\ninvoice_number or invoice_id: only one should be specified\n\ntransactable: Prospect, Contact, Company with which to associate the transaction\n\ntransaction_type: debit or credit\n\nbank_account_type: operating or trust\n\npayment_method: credit_card, check, cash, paypal, venmo, trust_payment, debit_card, ach, or other" tags: - Payment Transactions parameters: - name: fields in: query required: false schema: type: string example: all responses: '200': description: OK content: application/json: schema: type: object examples: postCreateRefundTransaction: summary: POST Create Refund Transaction value: data: id: '38' type: transaction attributes: account_type: Contact bank_account_type: operating payment_method: invoice_refund transaction_type: debit amount_cents: 5000 amount_currency: USD account_id: 112 external_id: null created_at: '2022-12-27T13:15:25.890-08:00' updated_at: '2022-12-27T13:15:25.890-08:00' note: '' relationships: created_by: data: id: '5' type: user account: data: id: '112' type: contact prospect: data: id: '113' type: prospect invoice: data: id: '1' type: invoice trust_fund_request: data: null refunded_transaction: data: id: '30' type: transaction postCreateTransaction: summary: POST Create Transaction value: data: id: '36' type: transaction attributes: account_type: Contact bank_account_type: operating payment_method: credit_card transaction_type: credit amount_cents: 5000 amount_currency: USD account_id: 112 external_id: null created_at: '2022-12-27T13:09:52.790-08:00' updated_at: '2022-12-27T13:09:52.790-08:00' note: '' relationships: created_by: data: id: '5' type: user account: data: id: '112' type: contact prospect: data: id: '113' type: prospect invoice: data: id: '1' type: invoice trust_fund_request: data: null '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 `.' 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.'