Simply put, yes. This is called voluntary registration. Once you’ve registered you must charge VAT on your supplies from your effective date of registration onwards. If your business has a taxable turnover of £85,000 you must register for VAT.
You must register for VAT if you expect your VAT taxable turnover to be more than £85,000 with in the next 30 day period, you must register by the end of the end of that 30 day period. Your effective date of registration is the date you realised, not the date your turnover went over the threshold.
If your business had a VAT taxable turnover of more than £85,000 over the last 12 months, then you also must register. You have to register within 30 days of the end of the month when you went over the threshold. Your effective date of registration is the first day of the second month after you go over the threshold.
If you are late to register you will have to pay what you owe from when you should have registered, you may also get a penalty depending on how much you owe and how late your registration is.
This page is not actively updated, some information may be out of date and should not be used for professional advice.