On 25 June 2010 the land counsel of Lower Saxony decided that the A22 will be renamed to A20 to show it is a lengthening of the Ostsee- or Küstenautobahn.

Construction started in 1992, only two years after the German reunification, near the junction Wismar-Nord and was completed in December 2005, when the last section was opened near Tribsees by Chancellor Angela Merkel.

On 28 July 2009 the western extension started with the opening between Autobahnkreuz Lübeck and junction Geschendorf.

[needs update] Further extension west (designated A 22 until June 2010) is planned and awaiting funding, including a tunnel under the Elbe and a 2-way connection with the also-planned A 26.

Details of the trajectory are being discussed in the counties and municipalities involved; the projected start of construction is said to be around 2013.