Implementing sustainable heating solutions in municipalities is crucial for a climate-friendly energy supply, with heat production being responsible for about 40% of CO2 emissions. In the German context, the recent legislation on local energy transition in heating heightens the pressure on stakeholders, including municipalities and local energy suppliers, to find sustainable supply solutions. Key technologies for the implementation of a more sustainable heat supply are district heating and household heat pumps, the latter introducing a sector coupling effect between heat and electricity. This sector coupling effect necessitates an approach that addresses an integrated planning of heat and electricity supply for heating purposes. The research aims to develop a method that supports decision-makers in strategically building or expanding district heating and electricity networks. Multi-year time horizons are considered to allow for a realistic gradual expansion planning while taking also into account short-term decisions by individual homeowners, such as adopting household heat pumps.