How does buying a home together with someone else work in Sweden?

You apply together and both become jointly and severally liable ("solidariskt ansvariga") for the entire loan. The bank adds up your incomes and debts. Decide ownership shares ("ägarandelar") – for co-ops specify this in the transfer agreement ("överlåtelseavtal"), for properties it's shown on title ("lagfart"). Create a cohabitation agreement ("samboavtal") or co-ownership agreement ("samäganderättsavtal") regulating what happens if you separate or someone wants to sell, especially if you contributed different amounts to the down payment ("kontantinsats"). This protects both parties and prevents conflicts about who paid what.