KintsugiKintsugi
API reference / Changelog

API changelog

Every change to the Kintsugi API and every release, newest first. Breaking changes carry the Breaking change mark. Tenanted releases are dated, and you choose one with the Api-Version header.

Changes

2026-10-07

Updates an organization's bank details
NewOrganizations

PATCH /bank-details changes bankName, accountNumber, accountType (CHECKING or SAVINGS), accountHolderName and routingNumber. A field you leave out keeps its stored value, a field sent as null is cleared, and the record is created when none exists. Text values are trimmed and cannot be blank, bankName holds up to 100 characters, and an unknown field is refused. The response never returns full numbers: accountNumberLast4 and routingNumberLast4 hold the last four characters, or **** for a number of four characters or fewer, and are null when not captured. A user must be an Owner or Admin of the organization; an API key that reaches the organization is accepted. Select the organization with Organization-Id, Connection-Id or Entity-Id.

What to do
  • Send only the fields you want to change, and null for one you want to clear.

2026-10-05

Adds filing metrics to the organizations list
NewOrganizations

GET /organizations accepts expand=filingMetrics, which adds a filingMetrics object to each organization: totalFilings, filed, pendingApproval (unfiled returns not yet past their due date), overdue (unfiled returns past their due date) and liabilityByCurrency, one { currency, amount } entry per currency. Returns marked do not file are left out of pendingApproval and overdue. Currencies are listed in code order, with returns that have no currency yet last as currency: null, and amounts are decimal strings that are never converted between currencies. An organization with no returns gets zero counts and an empty liabilityByCurrency. Without expand the response is unchanged, an unknown expand value answers 422, and a cursor stays valid with or without expand.

What to do
  • Pass expand=filingMetrics to get each organization's filing status in the same call as the list.

Releases

2026-10-06

LatestTenanted API

Consistent country codes, empty values and status casing

2026-10-06 makes the Tenanted API more predictable to build on. Every country code is now countryCode, a value that is not set is null rather than an empty string, and status and type values are uppercase throughout. Integrations pinned to 2026-07-21 are unaffected until you choose to move, and the table below lists everything that changes when you do.

Compared with 2026-07-21

ChangeApplies to2026-07-212026-10-06
Country code fieldAddresses, customers, transactions, tax estimates and billing usage, in requests and responsescountrycountryCode. Query parameters named country keep their name.
State on nexus exposure eventsGET /nexus/{nexus_id}/exposure-historystatestateCode, always present
State of a country-level filingstateCode and stateName on every filingEmpty stringnull
Organization state and country when not setstate and countryCode on organizations, and state in organization listsEmpty string, always presentnull, and may be omitted
Exemption with no match on a certificate uploadexemptionId on missing-certificate upload resultsEmpty stringnull
Missing-certificate status valuesUpload, upload status and public confirm-upload resultsLowercase: processing, satisfied, rejectedUppercase: PROCESSING, SATISFIED, REJECTED, plus PENDING on the public landing page
Exemption type when approving certificate importsPOST /certificate-imports/{certificate_import_id}/approve and POST /certificate-imports/bulk-approveAny text, defaulting to customerCUSTOMER, WHOLESALE, TRANSACTION or REVERSE_CHARGE, defaulting to CUSTOMER. Any other value returns 422.
Security questions in a credential revealfields on POST /registrations/{registration_id}/credentials/revealsecurity_questionssecurityQuestions
Line item with no product nameproductName on transaction linesnullEmpty string
Help article label on back-filing optionsGET /filings/backFilingRequest/optionsText or nullAlways text
Job ID on bulk filing resultsPOST /filings/bulk/approve and POST /filings/bulk/pausejobId, always nullRemoved

Moving an integration from 2026-07-21

  1. Send Api-Version: 2026-10-06 with each request you move. Requests without it keep running against 2026-07-21.
  2. Rename country to countryCode wherever you send or read an address, customer, transaction or tax estimate.
  3. Treat null as "not set" for filing and organization locations and for an unmatched exemptionId, and an empty productName as "no product name".
  4. Compare missing-certificate statuses in uppercase, and send exemptionType in uppercase when you approve certificate imports.
  5. Read stateCode on nexus exposure events, request securityQuestions when you reveal registration credentials, and stop reading jobId on bulk filing results.

2026-07-21

Tenanted API

Introducing the Tenanted API

A fresh foundation for building on Kintsugi. The Tenanted API is versioned by date, and you choose the release you build against. It speaks one consistent dialect from end to end: clean paths, camelCase fields, exact decimal amounts, and a single error format. And it is built for scale, with one credential reaching every organization it owns.

Compared with v1

Topicv12026-07-21
VersioningThe /v1 path prefixThe Api-Version header, dated YYYY-MM-DD. Optional; without it, a request runs against the launch release
Paths/v1/transactions/transactions
Authenticationx-api-keyApi-Key. Endpoints that manage people accept a signed-in session token instead
Choosing an organizationx-organization-id, required on almost every requestOne credential reaches every organization it owns. Narrow a request with Organization-Id, Connection-Id, or Entity-Id
Field namessnake_casecamelCase
Money and ratesDecimal strings out, numbers or strings inDecimal strings at a fixed scale: amounts to 2 places, rates to 9
TimestampsNo single documented formatRFC 3339 in UTC, always ending in Z
ErrorsShapes vary by endpointOne envelope everywhere: code, message, requestId, and errors
PortfolioNot availablePortfolio and Portfolio Reseller endpoints, for partner accounts

Moving an integration from v1

  1. Send Api-Version with every request, pinned to the release you build against (the newest is 2026-10-06), so your integration stays on it until you decide to move.
  2. Drop /v1 from your paths.
  3. Send your key as Api-Key, and replace x-organization-id with Organization-Id wherever you target one organization.
  4. Rename fields to camelCase, and read every amount as a decimal string, never a float.
  5. Branch on the error code, not the message or the HTTP status, and quote requestId when you contact support.

Creating a transaction answers 202 Accepted straight away, and tax is calculated just after. Check processingStatus before you read the tax totals.

v1

Legacy

The original Kintsugi API, versioned in the path. It is documented exactly as before, so existing integrations can keep running with confidence. New integrations should start on the newest Tenanted API release.

Kintsugi API Changelog