McDonald's has beaten Wall Street estimates for comparable sales and said it returned to pre-pandemic levels of growth, driven by eased Covid-19 restrictions in some markets and US customers - flush with stimulus cash - craving new chicken meals.

First-quarter global comparable sales growth of 7.5% surpassed pre-pandemic 2019 levels, chief executive Chris Kempczinski said.

That trounced the 4.71% growth expected by analysts polled by Refinitiv IBES data.

The fast-food chain also raised its 2021 systemwide sales outlook to the mid-teens from the low double-digits.

An intense vaccination drive and the distribution of relief checks encouraged more people in the US to eat out.

Fast-food chains have managed to weather pandemic restrictions much better than others in the industry, given their drive-thrus, delivery networks and competitive pricing.

McDonald's also rolled out its crispy chicken sandwiches earlier this year in the US, looking to tap into a frenzy kicked off by privately owned Chick-fil-A and Restaurant Brands International's Popeyes in 2019.

Those factors, combined with celebrity marketing campaigns, helped power a 13.6% jump in sales at restaurants open for more than a year, beating expectations of 9.25%, according to the analysts.

Sales were driven in part by higher checks, with traffic lower across all segments.

McDonald's also showed strong growth in its international markets, with the UK, Australia and Canada recording a rise in sales.

However, Covid-19 resurgences in some markets led to volatility and new government restrictions, particularly in France and Germany.

Shares of the company were marginally lower before the opening bell, after gaining about 8% so far this year.

The company's net income rose to $1.54 billion, or $2.05 per share, for the first quarter, from $1.11 billion, or $1.47 per share, a year earlier.

Revenue increased 9% to $5.12 billion, above estimates of $5.03 billion.

Excluding one-time items, the company earned $1.92 per share, well above the expectation of $1.81.