When the children were smaller we applied and received some tax credit money which came in very handy. For the past few years we haven't bothered applying as the amount owing was something like £30 a year and it did not seem worth it, especially as you have to pay the money back if the calculations were wrong. The amount you receive is based on your previous year's earnings so when I got this year's letter I thought that it wasn't worth applying as our income last year was still too much to qualify.
However, I read the letter again and it said to contact the authorities if your income had changed for the year 2017-18. Well, our income has gone down a lot so I thought that it was worth making a telephone call and ask for an estimate based on what I think we will get this year. The person on the other end of the line was very helpful and at the moment we will be entitled to the maximum amount for MasterShoestring. This will change if our earnings go up but otherwise we can expect over £200 every 4 weeks !
I was so glad that I had bothered to call and ask rather than just assuming we would have to wait until next year. It is worth periodically re-examine to see if you are claiming all your tax allowances as you never know you might be entitled to more !