A NOTE OF CAUTION PLEASE!
There are a number of companies offering to submit your MTD data for you and request that you send them your accounts data file. Under current GDRP (General Data Protection Regulations) you could be in breach of these regulations if you shared your sensitive contact data to any third party without express permission of each contact concerned to do so. There is also a security risk. Don’t risk being prosecuted and fined by the Information Commissioner or to having your sensitive data compromised!