Directly in BT Pay, in the Investments section, if you are a BT customer, or on the BT Pensions website, in the 'My account online' section, you can check at any time how much money you've contributed so far, how much money you've accumulated and how your money is performing. 😃 

In addition, each year you will receive a letter (by e-mail or to your postal address) with details of last year's contributions and the value of your personal assets at the end of the previous year.