Rantzau (Amt)

{{Infobox settlement

| name = Rantzau

| native_name =

| native_name_lang = de

| settlement_type = Amt

| image_flag = Flagge Amt Rantzau.png

| image_shield = DEU Amt Rantzau COA.svg

| image_seal =

| image_map = Amt Rantzau in PI.svg

| map_caption = Map of district of Pinneberg highlighting Rantzau

| coordinates =

| coor_pinpoint =

| coordinates_footnotes =

| subdivision_type = Country

| subdivision_name = Germany

| subdivision_type2 = State

| subdivision_name2 = Schleswig-Holstein

| subdivision_type3 = District

| subdivision_name3 = Pinneberg

| established_title =

| established_date =

| extinct_title =

| extinct_date =

| seat_type = Region seat

| seat = Barmstedt

| leader_party =

| leader_title = Amtsvorsteher

| leader_name = Matthias Bagger

| area_total_km2 = 112.0

| population_footnotes =

| population_total = 8,905

| population_as_of = 2020-12-31

| population_density_km2 =

| website = [http://www.amt-rantzau.de/ www.amt-rantzau.de]

}}

Rantzau is an Amt ("collective municipality") in the district of Pinneberg, in Schleswig-Holstein, Germany. It is situated around Barmstedt, which is the seat of the Amt, but not part of it. The Amt was named after the County of Rantzau, which existed between 1649 and 1864.