Going the extra mile
This is an extended delivery order. Delivery times and fees may be higher.
About Flat Out - Smash Burgers - Royal Docks
Expertly smashed, just for you. Your Flat Out journey begins at the iconic crispy edge of our patties, taking you on a tantalising trip to a juicy centre. We keep the toppings simple, delicious and customisable for you. We use quality certified British & Irish beef that's sourced carefully to halal standards - because we believe everyone should be able to enjoy our proper smashed burgers. Choose between one, two, three, four and even TEN patties - how high will you go?
30% off selected items
Get 30% off selected items – T&Cs apply. New customers only.
BBQ Onion Burger
Two juicy smash patties layered with smoky cheddar and American cheese, with delicate, thinly sliced onions tucked between the patties for a burst of fresh flavor. Topped with crispy fried onions, BBQ sauce, our signature house sauce, and crisp lettuce—all nestled in a perfectly toasted bun.£7.35£10.50Popular30% offDouble Cheeseburger
The champ - a truly undefeated burger. Two mighty fine crispy smashed patties with THREE slices of melted American cheese, diced onions, gherkins and your choice of our delicious house sauce or that classic combination of ketchup and mustard£6.23£8.90Popular30% offSpicy Jalapeño Burger
Two juicy smash patties layered with smoky cheddar and melty American cheese, topped with a kick of chilli jam, fiery jalapeños, crispy lettuce, and our signature house burger sauce, all packed into a soft, toasted bun. Bold, spicy, and irresistibly good!£7.35£10.50Popular30% offVegan Double Cheeseburger 🌱
Indulge in our Vegan Double Smash Burger, a plant-based delight that doesn't compromise on flavor. Featuring two perfectly seasoned, crispy-edged vegan patties, topped with refreshing pickles, crunchy onions and a tangy vegan special sauce. All this goodness is sandwiched between a toasted, soft vegan bun.£6.93£9.90Popular30% off
Popular with other people
The Flat Out Combo
£14.50Gooey Mac & Cheese Bites
£4.50Triple Cheeseburger
£11.90Churros
£4.90Hot 'n' Gooey Mac & Cheese Bites
£4.50Singles Feast
£17.00Single Cheeseburger
£6.90Quadruple Cheeseburger
£14.90The Flat Out Feast
£28.90Vegan Triple Cheeseburger 🌱
£12.90
Meal Deals 🤑
Fun, love & burgers. Oh, and your choice of sides and drinks too.
The Flat Out Combo
Making life easy for you. Our classic double cheeseburger with your choice of a delicious side and drink.£14.50PopularSingles Feast
A mouthwatering smashed burger, paired with a side, a refreshing drink, and finished with indulgent caramel-filled churros served with rich chocolate dipping sauce. The perfect solo treat for a feast of flavors!£17.00The Flat Out Feast
For those who like to live life large. Double up on our classic double cheeseburger alongside your choice of TWO delicious sides and TWO thirst quenching drinks£28.90
Seasonal Specials 🍂
Discover our two new smash burgers: expertly crafted, bold, and delicious—here for a limited time only!
BBQ Onion Burger
Two juicy smash patties layered with smoky cheddar and American cheese, with delicate, thinly sliced onions tucked between the patties for a burst of fresh flavor. Topped with crispy fried onions, BBQ sauce, our signature house sauce, and crisp lettuce—all nestled in a perfectly toasted bun.£7.35£10.5030% offSpicy Jalapeño Burger
Two juicy smash patties layered with smoky cheddar and melty American cheese, topped with a kick of chilli jam, fiery jalapeños, crispy lettuce, and our signature house burger sauce, all packed into a soft, toasted bun. Bold, spicy, and irresistibly good!£7.35£10.5030% off
Burgers 🍔
Burgers that are smashed for flavour and texture. How high will you go?
Double Cheeseburger
The champ - a truly undefeated burger. Two mighty fine crispy smashed patties with THREE slices of melted American cheese, diced onions, gherkins and your choice of our delicious house sauce or that classic combination of ketchup and mustard£6.23£8.9030% offTriple Cheeseburger
The three-peat - only for the true burger greats. Three mighty fine crispy smashed patty with FOUR slices of melted American cheese, diced onions, gherkins and your choice of our delicious house sauce or that classic combination of ketchup and mustard.£11.90Quadruple Cheeseburger
The Quad - for those who want it all in their burger. Four mighty fine crispy smashed patties with FIVE slices of melted American cheese, diced onions, gherkins and your choice of our delicious house sauce or that classic combination of ketchup and mustard.£14.90Single Cheeseburger
The underdog of burgers - never to be underestimated. One mighty fine crispy smashed patty with two slices of melted American cheese, diced onions, gherkins and your choice of our delicious house sauce or that classic combination of ketchup and mustard.£6.90
Vegan Burgers 🌱
Savor the flavor-packed delight of our Vegan Smash Burger, a plant-based patty cooked to perfection and bursting with taste in every bite.
Vegan Double Cheeseburger 🌱
Indulge in our Vegan Double Smash Burger, a plant-based delight that doesn't compromise on flavor. Featuring two perfectly seasoned, crispy-edged vegan patties, topped with refreshing pickles, crunchy onions and a tangy vegan special sauce. All this goodness is sandwiched between a toasted, soft vegan bun.£6.93£9.9030% offVegan Triple Cheeseburger 🌱
Treat yourself to the ultimate plant-based feast with our Triple Vegan Smash Burger! This towering creation features three juicy, perfectly smashed vegan patties, each layered with melted vegan cheese. Topped with tangy pickled gherkins and diced onions, all nestled in a soft, toasted vegan bun.£12.90
THE FLAT OUT CHALLENGE 💪
A burger to end all burgers. Post a before & after shot on your Instagram story, tag @flatoutburgersuk, and you'll receive £10 off your next order. That's a pound for every patty! Do you have what it takes?
Ten Patty Cheeseburger Challenge
TEN mighty fine crispy smashed patties & ELEVEN slices of gooey American cheese* in this ultimate burger challenge. *with diced onions, gherkins and your choice of house sauce or ketchup and mustard too.£29.90
Sides 🍟
Beige but beautiful.
House Waffle Fries
Death to soggy chips. Long live crispy waffle fries - lightly seasoned with salt because that's all you need.£3.90Hot Waffle Fries
Dusted in our house seasoning to give you that kick you're craving when you're going flat out.£3.90House Tater Tots
Pure nostalgia. Like hash browns, but so much better.£3.90Hot Tater Tots
Tater tots tossed in our house seasoning.Top tip: best enjoyed dunked in our ranch or house sauce.£3.90Gooey Mac & Cheese Bites
Bites of macaroni pasta - crumbed & coated in our original seasoning and oozing with mature cheddar cheese inside. Naughty.£4.50Hot 'n' Gooey Mac & Cheese Bites
Bites of macaroni pasta - crumbed & coated in our HOT seasoning and oozing with mature cheddar cheese inside. Do yourself a favour and dunk these in some of our ranch or house sauce.£4.50Cheeseburger Waffle Fries
Our iconic waffle fries topped with smashed crispy pieces of beef, melted cheese sauce, pickles and crispy onions. Peak indulgence.£9.00
Sauces & Dips 🍅
Dunk away.
Cajun Ranch Sauce
House-made, smoky, creamy and blackened with cajun seasoning. A Flat Out team favourite.£0.90House Sauce
Our secret house sauce. It's creamy. It's tangy. It's addictive.£0.90Ketchup
Heinz. Say no more.£0.90
Drinks 🥤
The classics only.
Coke Zero
The OG minus the sugar.£2.25Coke
The OG.£2.25Rubicon Mango
Currently sold out£2.25Fanta Orange
Fizzy orange for that juicy fix.£2.25Sprite
Fun fact: our lowest selling drink. Show it some love.£2.25
Dessert 🍦
Finish on something sweet.
Churros
Caramel-filled churros with a rich chocolate dipping sauce. A perfect, sweet finishing touch!£4.90
