Your obligations under the Data Protection Act
The amount of information about customers that you hold will vary between individuals, but at the very least, to comply with your Income Tax record keeping obligations, you should retain copies of all your sales invoices. These will probably record the customer’s name and address (and possibly email address and telephone number).
The Data Protection Act requires that any data you hold must be:
* processed for specific purposes,
* relevant and not excessive,
* accurate and up to date,
* not kept for longer than is necessary, and
* kept secure.