CHICAGO — Digital system-wide sales across McDonald’s Corp.’s top six markets were nearly $8 billion during the first six months of 2021, a 70% increase versus last year, according to Christopher J. Kempczinski, president and chief executive officer. The sales surge comes as more restaurants around the world are reopening dining rooms and has management optimistic about the rest of the year.

“We know that the customer experience today reaches beyond the physical walls of our restaurants,” said Mr. Kempczinski during a July 28 conference call to discuss financial results. “And that's why we're accelerating the Arches to better serve our digitally connected customers. To give you a sense of the growing digital connection we have to our customers, we have the most downloaded QSR app in the United States.”

McDonald’s net income for the first half of fiscal 2021, ended June 30, was $3.8 billion, equal to $5 per share on the common stock, and a jump from the same time of the previous year when the company earned $1.6 billion, equal to $2.12 per share.

First-half sales, excluding currency translation, rose 25% to $11 billion. The jump in net income and sales reflected very different market conditions as many markets around the world had closed or limited restaurant operations during the early days of the pandemic.

Second-quarter net income was $2.2 billion, equal to $2.95 per share, and up significantly over the year prior when earnings were $484 million, equal to 65¢, per share.

Quarterly sales were up 49% to $5.9 billion.

“… Global comp sales were up 40% in the second quarter or 7% on a two-year basis,” said Kevin M. Ozan, chief financial officer. “Our performance has continued demonstration of the broad-based strength and resiliency of our business. We've surpassed 2019 sales levels for the second consecutive quarter and now at an accelerated rate.”

In the US, comparable sales increased 15% on a two-year basis, reflecting continued momentum, according to the company.

“Our performance in the US is the result of an accumulation of decisions that we've made over the last 18 months,” Mr. Ozan said. “This includes bold marketing initiatives, investing in the core menu and strengthening our digital offerings with an underlying focus on running great restaurants.

“As customers in the US began to venture out more during the second quarter, we continued to see strong average check growth driven by larger order sizes and menu price increases. That's been bolstered by growth in delivery and digital platforms as well as robust menu and marketing programs.”

McDonald’s launched the MyMcDonald’s Rewards app and loyalty program in the US in early July. More than 22 million users have logged into the app, and more than 12 million have enrolled in the loyalty program, according to the company.

“This is just the beginning of the digital customer journey at McDonald's,” Mr. Kempczinski said. “As we create more personal and seamless McDonald's experiences and make it easier for our crew to connect with our customers, we're giving customers multiple reasons to continue to come back to McDonald's. By using digital, we'll also leverage our advantages in value and convenience, daypart and menu breadth and our biggest advantage, our size and scale.”