The bright red post box has been placed in The Square by Shrewsbury Business Improvement District, alongside a large Christmas tree taking pride of place under the Old Market Hall.
A letter template can be downloaded from the Original Shrewsbury website which children can use to ensure they receive a reply from Father Christmas himself.
As well as the Letters to Father Christmas campaign, local musicians will be playing tomorrow, Saturday and on December 16, 18, 19 and 22 to provide some extra festive atmosphere.
The town will also be lit up with not only the traditional Christmas lights, but a special festive lighting project by Shrewsbury-based projectionist Andy McKeown.
Emma Molyneux, of Shrewsbury BID, said it was all part of an effort to make the town centre feel fun and welcoming, as well as being safe, for people to do their Christmas shopping.
“This is certainly a Christmas like no other, and we want to do as much as we can to help people enjoy spending time in the town centre,” she said.
“Safety is of course the number one priority, but we hope that providing live music, exciting lighting displays and letters to Father Christmas will help create a lovely festive atmosphere.
“Specially-designed templates for letters can be downloaded from the Original Shrewsbury website, or children are welcome to write their own letters without a template – just remember to include an email address so Father Christmas can reply!
“We would like to thank Shrewsbury Town Council for all their work on the lighting displays, which look absolutely fantastic.”
Town centre traders are being encouraged to join in with the festivities by decorating their windows as part of the shop window competition.