McDonald's has clarified only certain restaurants are participating in the Eat Out to Help Out scheme.
As of this week, customers can get big discounts at a range of restaurants from Monday to Wednesday.
It means throughout August, anyone dining in a McDonald's restaurant will be able to get half price food - which is already cheap as chips thanks to VAT cuts.
But, because qualifying meals must be consumed inside, takeaway meals will not have their prices slashed.
The scheme is designed to boost dine-in restaurants that have been shuttered for several months during the coronavirus crisis.
But it seems not everyone has got their head around the rules, with the chain's social media receiving messages from confused customers.
In response to one person asking "where's my half price food?", the fast food chain tweeted out: "We are participating in the Government's Eat Out To Help Out scheme.
"This scheme only applies when you dine in at a participating branch.
"This does not apply for Drive Thru, Takeaway, or McDelivery."
Anyone eating at a participating business on Monday, Tuesday or Wednesday in August will automatically get 50% off the price of food and non-alcoholic drinks, up to a maximum of £10 per person.
There is no minimum spend and the discount can be used at the same time as other offers and discounts.
All diners, in a group of any size, will qualify for the automatic discount, you don't need to do anything to get it. HM Revenue and Customs will pay the discounted cost back to the restaurant.
