Hemnet said it expected third-quarter sales to grow above its financial target of 15-20%, but "clearly moderate" from the second quarter, which benefited from a favourable year-ago comparison.
Swedes have been seeking more space for working at home during the pandemic, leading to higher demand for houses and large apartments and more people using Hemnet's website.
"It has been an exceptional quarter," CEO Cecilia Beck-Friis told Reuters, adding the company was also helped by a new pricing model and new products for property sellers.
Second-quarter sales rose 47% to 212.5 million crowns ($24.05 million), while adjusted operating profit before depreciation and amortisation (EBITDA) surged 104% to 111 million crowns.
Hemnet shares, which by Thursday had risen more than 50% since listing on Nasdaq Stockholm in April, were up 13.6% at 0834 GMT.
The company said the number of listings grew 19% year-on-year in the quarter.
Swedish house prices have surged during the coronavirus pandemic and are up 17% in the past 12 months, according to the Nasdaq OMX Valueguard-KTH Housing Index (HOX).
Founded in 1998, Hemnet was acquired by General Atlantic and Sprints Capital in 2016.
($1 = 8.8370 Swedish crowns)
(Reporting by Helena Soderpalm, editing by Niklas Pollard and Susan Fenton)
By Helena Soderpalm