Is it legal for water utilities to charge you a late fee within 10?
Read the terms of your contract of the water authority. Terms of Payment will probably be somewhere near the end of the small print but it will clearly state on what basis overdue charges are assessed. Usually late payment terms are based on the date of the invoice, not the date of receipt. If you had problems with postal delivery or you have a remote location where postal service is irregular or erratic then maybe you should switch to electronic billing or payment of utility charges by standing order to your bank (also known as domiciliation). If you route your utility and telecom bills (and anything else that is regular and frequent, such as insurances or mortgages and rental payments) through your bank account, you dont have to worry about payments being on time any more and you can always challenge errors afterwards.