# JPMC-PDP Documentation from https://developer.payments.jpmorgan.com

# Routing preference

The `merchantPreferredRouting` field allows you to specify your preferred routing model for debit card transactions, including PINless debit and eftpos Australia. This field is central to merchant-directed routing, enabling you to optimize transaction costs and routing outcomes.

## Merchant-directed routing

When submitting a transaction with merchant-directed routing, consider the following guidelines:

- Send merchantPreferredRouting with CREDIT or PINLESS on each transaction request.

- We route the transaction according to your preference.

- If you omit merchantPreferredRouting, we route based on card eligibility.

- If the requested route is not supported for the card, the API returns an error.

## Acquirer-managed routing

When submitting a transaction with acquirer-managed routing, consider the following guidelines:

- Send accountNumber and omit merchantPreferredRouting.

- We determine the optimal routing based on card eligibility.

- If the card is eligible for PINless debit, we route the transaction as PINless debit.

- If you provide a routing preference that is not available for the card, we reassign the transaction to an eligible routing option.

- Because routing can change, include all required fields for both credit and debit processing in the request.