It's a staple of Western budgeting advice: eat in if you want to save money. But in many parts of Asia, Africa and Latin America, the maths turns on its head. Here, cooking is often the luxury and dining out is the economical choice, thanks to factors such as lower overheads, lighter regulation and intense competition.

From Vietnam, with its legendary street food vendors, to Mexico, home to the much-loved cocinas económicas, read on for 10 global destinations where your wallet is better off if you never turn on the stove.

All dollar values in US dollars

In richer economies, restaurants face high rents, wages, utility bills, stricter regulation and other stiff overheads, so menu prices often run several times the cost of ingredients, especially once drinks are included. Many budget eateries are chain-run and carry franchise and marketing costs, while also offering broad menus, which increase food waste.

By contrast, supermarkets operate at huge scale with intense competition and thin margins, keeping groceries relatively cheap.

In many developing economies, independent low-cost restaurants and street vendors operate with fewer regulations and minimal overheads, from rents to labour costs. They buy ingredients in bulk and focus on a small number of high-volume, near-zero-waste dishes, allowing them to survive on tiny margins. Because eating out is the norm, turnover stays constant and competition is fierce.

Meanwhile, groceries can be relatively expensive and refrigeration or affordable domestic energy limited, pushing up the cost of cooking at home.

Now let's take a look at the countries where eating out is cheaper.

In Thailand, urban homes are often with built with a tiny kitchen or none at all because eating out is the more economical option. Forget global fast-food chains, which many Thais view as expensive. The nation's roadside vendors and low-cost neighbourhood restaurants serve staples like pad thai for as little as $0.30 (22p), undercutting the cost of retail groceries.

Supermarkets in the country are notoriously expensive, and even shopping in local markets can prove costlier since households buy small quantities while vendors purchase in bulk from wholesalers.

In Vietnam, eating out is also part of everyday life rather than a treat. From bánh mì sandwiches to bowls of comforting pho, meals can cost well under $1 (74p).

As is the case in neighbouring Thailand, busy street kitchens specialise in just a few dishes and cook them all day, keeping prices extremely low. With groceries sold in small quantities and home kitchens often basic, grabbing a bite to eat outside is frequently the most sensible option.

Taiwan reportedly eats out more than any other nation. Homes without kitchens are commonplace and many people in the country go months without ever turning on a stove. Cheap bento boxes, noodle shops and night-market stalls feed people daily, with high turnover keeping prices remarkably low.

With groceries comparatively expensive in the country, heading out for breakfast, lunch and dinner makes much more sense economically.

As a rich nation where it's often cheaper to eat out, Singapore is a stark outlier. The city-state's famous open-air food courts, known as hawker centres, are treated as part of the national identity and recognised by UNESCO, so the government protects them through subsidised rents, grants and purpose-built complexes that drastically lower overheads.

Dense neighbourhoods and constant demand mean high turnover, fierce competition and little waste, keeping prices dramatically low. In fact, a plate of Hainanese chicken rice, the nation's most iconic hawker dish, can be picked up for just $0.79 (58p).

Across the Philippines, everyday meals often come from small roadside canteens called carinderias, rather than domestic kitchens. An ulam (main dish) can cost as little as $0.17 (13p), challenging the economics of cooking at home.

These eateries prepare large batches of familiar dishes and serve them cafeteria-style, keeping portion prices extremely low. With inexpensive labour and abundant staples such as rice and fish, the per-meal cost can fall below what many households can achieve themselves, especially for people living alone.

In Indonesia, everyday meals are often bought from warungs, small family-run food stalls found on nearly every street, many operating from the front of family homes to keep overheads low. Dishes like nasi goreng, noodles or rice with vegetables and chicken can cost around $1 (£0.74), frequently less than cooking at home.

With little business rent to pay and family labour doing the cooking, these kitchens can sell full plates at prices households struggle to match.

Throughout India, cheap canteens and street stalls sell plates of rice, breads and curries for less than many households would spend cooking them. With cooks buying from wholesale markets and serving the same dishes all day, prices stay strikingly low.

By way of example, an American family of five visiting Kolkata recently took to YouTube to share a full, hearty meal complete with dal, roti and raita that cost them under $3 (£2.20) all in.

Across Nigerian cities, lunchtime means queues at roadside bukas and neighbourhood cooks rather than pots on the stove at home. Plates of stew, beans or jollof rice are priced for daily workers and frequently work out cheaper than making the same dishes at home, especially for those who cook for one.

Vendors purchase supplies wholesale and cook in large batches, while the price of retail cooking fuel and gas along with ingredients can push household costs higher. For many urban residents, stepping out for a meal is simply the more affordable option.

Many Colombians depend on the corrientazo, a fixed-price set lunch served in small neighbourhood eateries. For not much more than the equivalent of a US dollar in some joints, diners get an entire meal, which often costs less than buying the ingredients individually. Given kitchens cook one menu for hordes of customers each day, they can keep prices extra-low.

For single people in particular, the daily set meal frequently works out cheaper than cooking at home.

In Mexico, budget neighbourhood restaurants called cocinas económicas and street-side taco stands often undercut home kitchens. Neighbourhood eateries serve full plates of rice, beans and meat for just a few dollars, while tacos can cost as little as about $0.60 (£0.44) each.

Again, costs are kept low by factors such as minimal overheads and bulk buying.

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