Mark, 28, and Michelle, 27, are expected to finally tie the knot this weekend in what will undoubtedly be the showbiz wedding of the year.
While their celeb guests should have no problem finding two amazing looks, the non-famous people are said to be struggling.
An insider claimed that as well as the actual ceremony, Mark and Michelle are having a photo shoot for select guests the next day.
The source told the Mirror: “The venue Mark and Michelle have chosen is incredibly posh – it’s like somewhere Lady Edith would get married.
“So guests attending the breakfast the following morning will still have to look swish. Obviously, the TOWIE girls have endless wardrobes but some of the other guests are stressing about needing two outfits.
“They know the wedding party will be full of glamorous people in expensive dresses so it has put the pressure on some non-celeb guests.
“It’s all going to be part of the magazine coverage so everyone wants to to look their best.”
The reality and soap stars said to be attending include James Argent, Lydia Bright, Elliott Wright and Brooke Vincent.