The Royal Mail‘s Print Postage Online service can save a huge amount of time if you’re sending something that falls foul of their arcane pricing structure. You can print out a personalised label, bung it on the envelope, and—if it’ll fit in a postbox—send it on its merry way all by yourself.
I’m not actually suggesting that you avoid this service altogether: it’s just too useful, and is to stamps what the debit card has become to pocketfuls of change. Clearly its use for ordinary post is a loss to Post Office branches, but there’s a way in which it actually costs them money. If you print a label for a service that requires the item to be handed in (like special delivery, so it can be barcoded and scanned on submission), your local post office gets absolutely nothing. As they have to spend time processing the item, which can take a few minutes, and then storing it on their premises, sending items in this way is directly detrimental to that branch.
Many smaller branches’ postmasters are not salaried, and only make a living through transaction commission. Sadly and bizarrely, handing in a pre-printed item for processing is not seen as a transaction: even though the branch does most of the work, they don’t actually make the sale.
Most people, especially in rural areas, are keen to support their local post office for themselves and their community. So do them a favour: if you need their help to send stuff, let them take your money. You’ll make a postmaster very happy.