The 31 July 2014 is the date that you should make your second payment on account to HMRC.
For example on 31 July 2014, you’d make your second payment on account for the 2013-14 tax year.
From the 31 July you will have to pay interest on anything you owe and haven’t paid, including any unpaid penalties, until HMRC receives your payment.
As well as the 4.54 million self-employed people in the UK, higher rate taxpayers, company directors and anyone with more than one income are required to make a payment on account – part of their annual tax payment.
Don’t forget to pay!
steve@bicknells.net
Business Accountant 
Wonderful post! We will be linking to this particularly
great article on our site. Keep up the great writing.