The 'Someone Like You' hitmaker, who took to Twitter for the first time in almost three months, said the couple are very much together.
"Just wanted to wish everyone happy holidays and all the best for 2015! PS Simon and I are still very much together, don't believe what you read," she tweeted.
There were reports that the couple were living apart, which sparked break-up rumours.
Adele, 26, who is known for keeping her personal life very private, and her partner Konecki have a two-year-old son Angelo.