Go-Ahead group swung to a £200,000 loss in the year to 27 June.
The loss is compared to a £97m profit in the same period a year earlier.
Shares in the group, however, rose slightly on Wednesday after the transport group said that regional services were back to 50-60% capacity.
Despite the fall in profits, total revenue grew 6.1% to £3.9bn.
Most of the losses are related to £30.4m due to failings in the German operations.
David Brown, the group’s chief executive, said: “Our financial results for the year have been significantly impacted by the pandemic despite only four months of the crisis period falling within our financial year.”
“While our German rail contracts have not been materially impacted by the crisis, this business continues to face significant operational and commercial challenges associated with the delayed delivery of trains and driver shortages.
“Through management action, we have seen operational performance improve and we have a clear plan to deliver profitability over the medium term.”
Go-Ahead’s basic earnings per share, before exceptional items, were down 69.5% to 51.6p.
Coach provider National Express also posted a loss on Wednesday as the travel industry was hit by the pandemic, however, shares rose after it traded “slightly above” its expectations.