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HMRC internal manual

Debt Management and Banking Manual

Interest: Interest on reallocations and repayments - by IT system: SAFE: Overview

SAFE will automatically calculate RPI on any reallocations within the system. Where the RPI itself contributes to an overall excess payment position for the customer the RPI together with other excess payments will be transferred to OAS to be repaid.

There is a function in SAFE that enables an RPI credit to be recorded on a customer record. This can arise where the automatic calculation of RPI in SAFE has been inhibited or the RPI credit has been created outside of SAFE and needs to be credited to the customer