> ## Documentation Index
> Fetch the complete documentation index at: https://docs.gettrxn.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Crypto payments overview

> How cryptocurrency payments work in TRXN.

TRXN enables businesses to accept cryptocurrency payments while managing pricing in fiat currency (USD). This page explains the end-to-end payment flow from defining products to allocating received funds.

## Payment flow

The cryptocurrency payment lifecycle consists of five stages:

<Steps>
  <Step title="Define products and prices">
    Account holders create products with fiat-denominated prices. Each price can optionally include a [slippage margin](/guides/slippage-margin) to accommodate crypto price volatility during payment confirmation.

    ```
    Product: "Pro Plan"
    └── Price: $99.00/month (USD)
        └── Slippage margin: 2%
    ```
  </Step>

  <Step title="Generate invoices">
    Invoices are created either manually or automatically from [subscriptions](/guides/subscriptions). Each invoice contains line items that reference products and prices, establishing the fiat amount owed.

    For recurring subscriptions, TRXN handles [invoice generation](/guides/invoice-generation) automatically based on billing cycles and phase schedules.
  </Step>

  <Step title="Assign crypto addresses">
    Payment addresses are generated or assigned for customers. Each customer has a wallet that holds one or more crypto addresses. When a customer needs to pay an invoice, the system provides the appropriate address for the selected cryptocurrency.

    ```
    Customer: Acme Corp
    └── Wallet
        ├── BTC Address: bc1q...
        └── ETH Address: 0x...
    ```
  </Step>

  <Step title="Verify payments">
    TRXN queries the blockchain to find transactions sent to the assigned address within the expected time window. For each transaction found, the system looks up the historical crypto-to-fiat exchange rate at the exact moment of the transaction and calculates the fiat value.

    See [Transaction verification](/guides/transaction-verification) for the full verification flow.
  </Step>

  <Step title="Allocate transactions">
    Verified transactions are allocated against outstanding invoices. A single transaction can be split across multiple invoices, and multiple transactions can be combined to satisfy a single invoice. The [slippage margin](/guides/slippage-margin) determines how much price fluctuation is tolerated before a payment is considered complete.
  </Step>
</Steps>

## Supported cryptocurrencies

TRXN currently supports:

* **BTC** (Bitcoin)
* **ETH** (Ethereum)

Each cryptocurrency uses blockchain-specific query providers and may have different price data sources.

## How fiat and crypto work together

TRXN takes a fiat-first approach to pricing:

1. **Prices are always defined in fiat** (USD). There is no need to set crypto-denominated prices that become stale as markets move.
2. **Conversion happens at verification time.** When a blockchain transaction is detected, TRXN looks up the historical exchange rate at the moment of that transaction to determine the fiat value.
3. **Slippage margin absorbs volatility.** A configurable tolerance percentage prevents invoices from being marked as underpaid due to minor price swings between payment initiation and confirmation.

## Key concepts

<CardGroup cols={2}>
  <Card title="Subscriptions" href="/guides/subscriptions">
    Multi-phase subscriptions with automatic invoice generation and flexible pricing.
  </Card>

  <Card title="Slippage margin" href="/guides/slippage-margin">
    Configure price fluctuation tolerance so small swings do not leave invoices underpaid.
  </Card>

  <Card title="Transaction verification" href="/guides/transaction-verification">
    How TRXN queries the blockchain and converts crypto amounts to fiat values.
  </Card>

  <Card title="Invoice generation" href="/guides/invoice-generation">
    How recurring invoices are automatically created from active subscriptions.
  </Card>
</CardGroup>