The Crime Contract specifically prevents you from charging for postage and stationary. The relevant bit is in the Criminal Bills Assessment Manual.

3. Guidance for all Assessments

3.1 Administrative Work and Overheads

1. Subject to any express exceptions, payment will not be made for time spent on purely administrative matters (5.54, of the SCC Specification). Thus, office overheads are not recoverable under the SCC. Overheads include, but are not limited to: the cost of maintaining premises, taxes, postage, stationery, typing, faxing, and telephone bills.

2. In deciding whether fee-earning work is administrative, consideration should be given to the work that was actually undertaken and not just the person doing the work. The test for fee-earning work is whether it goes directly to the provision of contracted legal services to the client.

3. The cost of undertaking all but exceptional quantities of photocopying in-house is regarded as an overhead expense (see Section 7).

4. Pursuant to 5.55, of the SCC Specification, the Assessor may not allow payment for preparing, checking, or signing a claim for costs. The cost of opening and setting up files, and maintaining time costing records are all administrative costs.

5. Courier fees are also excluded unless it is necessary to use a courier to deliver documents as a matter of urgency and the urgency has not been created by delay on the part of the solicitor.