The rule was implemented by DSB as a measure to reduce crowding on trains and thereby the risk of coronavirus spread.
But reservations will no longer be required as of Wednesday, the company announced.
Passengers are also free to decide whether to wear face masks on DSB services at their own discretion. Last week, health authorities changed official guidance, advising use of the protective item on busy public transport.
But the decision by DSB has been challenged by commentators in Denmark, given that Covid-19 cases in the country are currently increasing.
Health spokesperson with the Conservative party Per Larsen wrote on Twitter that he “did not understand” the move from DSB.
“Face mask recommendations have been introduced because it can be difficult to keep a distance during rush hour. Now DSB is removing the requirement that prevents overcrowded trains – and ensures passengers can keep their distance. Why?”, Larsen wrote, adding that he would take the issue up with health minister Magnus Heunicke.
DSB head of communication Tony Bispeskov defended the move, which comes at a time when Denmark is seeing its highest daily infection figures since May.
“We are doing this because the Danish Health Authority is now stating that it’s fine to travel on public transport. But when it is busy, and that will happen, you should wear a face mask. You can easily take the train and have a face mask in your pocket or bag and put it on if you don’t think it’s possible to keep a distance,” Bispeskov said to DR.
Seat reservations are not required for Metro and bus passengers, he also noted.
A further 112 confirmed cases of Covid-19 were registered in Denmark on Wednesday, according to figures from national institute SSI.
That reflects rising numbers, after 77 new cases were confirmed on Tuesday.
Wednesday’s figure is the highest number of daily registered cases of infection since May 8th, with the exception of Mondays, when infection figures for the preceding weekend are also published.