https://www.slab.org.uk/guidance/civil-legal-aid-accounts-availability-of-interim-payments-to-account-for-outlays/
There is guidance on how you can do this on Legal Aid Online in our accounts e-learning section.
General rules:
Reimbursements are paid only when a disbursement has been made/incurred and it is relevant to the grant of civil legal aid and where applicable; sanction granted. We aim to make any payment as quickly as possible but it may be necessary to seek further information. Providing a reimbursement does not mean we cannot later on decide that the payment is not properly allowable. If so, you will have to repay the money to the Legal Aid Fund.
Where the final civil account is submitted on paper it must contain a full and proper accounting of all work done and include all interim outlays paid previously. Where the account is submitted online only those outlays not charged by way of interim payments requires to be included in the account.
You can apply for interim payments of fees or outlays directly through Legal Aid Online or on paper.