I would like to know how much time it takes to get my luggage and get though passport check and then go from terminal 5 to terminal 3 in Heathrow airport. I'll arrive at terminal 5 at 8:15 am and my next flight leaves at 12 and the check in and bag drop closes one hour before the flight take off. I thought it was enough time but then I've read some posts saying you should plan at least 3 hours so I'm a bit worried now.
Thank you

Are you on two separate tickets or is your luggage checked through? Can you get checked through when you check in for the first flight so you dont have to exit security to check in for the 2nd?

Here is a guide on the Heathrow website that should provide guidance: http://www.heathrowairport.com/heath...ween-terminals

If I had my druthers, I'd give a day and a half.

Your 3.75 hour gap will probably work. It's going to take a good while to transport from T5 to T3 too.

Is it possible you can check yourself and your luggage through to your final destination? I assume you are arriving at T5 on a British Airways flight. Are you departing T3 on either another BA flight or a partner airline? If so, you can make your connection without leaving 'airside', and without going through immigration and collecting your luggage at baggage claim.

If you must transfer 'landside' for whatever reason, you will require more time, but in either case you should be fine. Just don't dawdle along the way. Assuming your flight arrives on time, you will have 3 hours 45 minutes.

my second flight is with virgin atlantic so I think I'll have to collect my luggage and get through immigration but I'm EU citizen so hopefully it won't be too long.

Check out the various youtube videos on the transfer.

You will still have to go through passport control when transiting from a non-Schengen country to a Schengen country.