The food-ordering firm lost $224 million for the first half of the year.
Analysts had forecast numbers well beyond that of around $256 million.
Strong order growth during lockdowns saw sales rise by just over a half to about $3 billion.
Chief executive Jitse Groen said that Just Eat Takeaway.com invested heavily in operations in the first six months of the year.
The company also repeated its full-year forecast for a loss of 1 to 1.5% of its gross transaction value.
Takeaway competes in various markets against the likes of Deliveroo and Uber Eats.
The firm said it aims to sell its 33% stake in iFood of Brazil, though it had rejected an offer of $2.7 billion.
