DB Network plans to double-track the 12km Niebüll - Klanxbüll section at the northern end of the route, which is used by frequent car shuttle trains between Niebüll and Westerland on the island of Sylt as well as regional and inter-city services. The €220m project is due to be completed by 2030.

In addition to track-doubling between Niebüll and Klanxbüll, the entire line will be modernised by 2022 at a cost of around €160m.

The ministry has also granted planning consent for the construction of a fourth platform at Elmshorn at the southern end of the line.