Södermanland County
- 🏛️ County seat: Nyköping
- 🌍 Region: Svealand,
East Middle Sweden (national area) - 📍 Location: borders Stockholm County, Uppsala County, Östergötland County, Örebro County and Västmanland County;
Lake Mälaren to the north, the Baltic Sea to the south-east - 📐 Area: 6,097 km² (land area)
- 👥 Population: 300,440 (Dec 31, 2025)
- ⛰️ Relief: fissure-valley landscape with many lakes, archipelago in the south
- 🗣️ Official language: Swedish
- ⏰ Time zone: CET (UTC +1, DST CEST +2)
- 💰 Currency: Swedish krona (SEK)
- 🌧️ Climate: temperate, with cold winters and warm summers
Municipalities in Södermanland County
Answers to frequently asked questions
What is the population of Södermanland County?
Södermanland County had 300,440 residents on December 31, 2025, up 1,039 (0.3%) from December 31, 2020 (Statistics Sweden).
What is the largest municipality in Södermanland County?
The largest is Eskilstuna with 106,789 residents, followed by Nyköping (58,310) and Strängnäs (39,387). Figures are for the municipalities on December 31, 2025 (Statistics Sweden).
How many municipalities are there in Södermanland County?
Södermanland County has 9 municipalities (Statistics Sweden, 2026). The smallest is Vingåker with 8,666 residents (Dec 31, 2025).
What is the county seat of Södermanland County?
The county seat is Nyköping, home of the County Administrative Board. Health care, public transport and regional development are run by Region Sörmland.
How many businesses are there in Södermanland County?
In 2024 there were 25,198 local business units in Södermanland County, 2.3% of the national total. The Statistics Sweden figure covers all industries except finance and insurance and public administration.
How large is Södermanland County?
The land area is 6,097 km², 1.5% of Sweden's land area (Statistics Sweden, 2025). Population density is 49 residents per km².