What is a Direct Debit Instruction (DDI) and DDI Reference?

**What is a Direct Debit Instruction (DDI)?**
A Direct Debit Instruction (DDI), sometimes called a Direct Debit Mandate, is the authorisation a customer provides to allow an organisation to collect payments from their bank account.

**What is a DDI Reference?**
A DDI Reference is a unique identifier created when a customer is set up in the L&Z system. It is lodged with the customer’s bank and must be included with every Direct Debit collection from that account.

**Can a DDI Reference be changed?**
Once created, a DDI Reference cannot be changed. To use a different reference, a new customer account must be created.

**Requirements for a DDI Reference in the L&Z system:**
- Must be between 6 and 108 characters
- Can be numeric, alphabetic, or a combination
- Cannot include spaces or punctuation

For further support, please contact customer.services@landz.co.uk.