Transaction flows

These pages map each step of an online order to the Taxwire call it needs. Start here, then follow the flow for your case:

Checkout and shipment: quote tax at checkout, record the sale when it ships.
Cancellations: an order cancelled before it ships, and a sale recorded by mistake.
Refunds: full and partial refunds of a recorded sale.
Pre-orders: orders paid now and shipped later.

The order, end to end

Blue boxes are Taxwire calls. Dotted lines are quotes, which save nothing. Thick lines record a transaction.

Quoting and recording

Every flow uses two calls:

Call	What it does	Saves anything?
`POST /calculations`	Quotes the tax for an order.	No. Call it as often as you like.
`POST /transactions`	Records a sale (`type: sale`) or a refund (`type: credit`). Recorded transactions are what Taxwire reports and files.	Yes.

Quote whenever the order changes. Record once, when the sale is complete. A quote that is never recorded has no effect on your returns.

Order steps at a glance

Order step	Call	Notes
Cart saved	None	A cart is not an order.
Checkout, and every change to the order	`POST /calculations`	Show the returned `tax_amount` to the buyer.
Payment	None	Charge the tax from the last quote.
Cancelled before shipping	None, or `POST /calculations`	Nothing was recorded. Quote the cancelled lines if you need the tax to refund.
Order ships	`POST /transactions`, `status: finalized`	Save the Taxwire `id` with your order.
Refund or return after shipping	`POST /transactions`, `type: credit`	Link it to the sale with `parent_transaction_id`.
Sale recorded by mistake	`POST /transactions/{id}`, `{"status": "void"}`	Only while the sale’s period is unfiled.
Delivery, settlement, payout	None	These don’t change the tax.

The API is synchronous and sends no webhooks. The response to POST /transactions is the saved transaction. See Retries and network failures for what to do when a request fails or times out.

Request basics

Every request uses the base URL https://api.taxwire.com and these headers:

Content-Type: application/json
X-API-Key: <your API key>
Taxwire-Version: hydrogen.2025-04-15

Amounts are strings in the currency’s smallest unit. "1000" is $10.00 in USD, and "45000" is ₩45,000 in KRW, which has no smaller unit.

Getting Started

Guides

API details

Calculations

Transactions

Customers

Certificates

Product Tax Codes (PTC) & Attributes

Products

Resources

Transaction flows

The order, end to end

Quoting and recording

Order steps at a glance

Request basics

​The order, end to end

​Quoting and recording

​Order steps at a glance

​Request basics

The order, end to end

Quoting and recording

Order steps at a glance

Request basics