Can I send money through the post
Sending money by post. It is perfectly legal to send money in the post, as long as the post office of the destination country is happy to accept cash sent this way. But Royal Mail stresses that cash and other valuables should not be sent in the ordinary mail. You should use Royal Mail Special Delivery Guaranteed®. This gives you some compensation if the post is lost or damaged (subject to correct declaration)
Money should be packaged securely and shouldn't be visible from the outside. Don't indicate anywhere on the packaging that money is enclosed.
Coins should never be sent in envelopes - our automated sorting machinery may damage envelopes containing coins, which can lead to delay in delivery and increase the likelihood of the contents being lost.