No, you do not need a letter and we do not issue students with any letters to travel home during vacation periods.
If there are no restrictions on you travelling during the vacation period, and as long as you return on or before the end of the vacation period date, then you will not be stopped by the UKVI.
If, for some reason, you are stopped then the UKVI will contact the university to confirm you are a student and we will do so.
If you are arriving after the end date of the vacation period then you will need permission to be away during term time and you should contact the International Office. Please note that if you attempt to travel without permission and are stopped then the University would be obliged to confirm that you are travelling without permission. The general term dates can be found at www.beds.ac.uk/aboutus/dates.
I am going to my home country during the vacation period. Do I need a letter?