The cost of living underwater

In response to the rising sea levels, our mortgage experts have investigated how much it would cost you to own a subaquatic property and the best spots to locate your sea view home.
Share this guide
A house for sale underwater

The cost of living underwater and where’s best to build

It’s no secret that sea levels are rising very quickly. In 2017, the US National Oceanic and Atmospheric Adminstration predicted that ocean levels would rise up to 8.2ft by 2100, and today, this seems like quite a moderate guess. Without any expensive infrastructure changes, an 8ft rise in sea levels would put most of New York, Washington DC, Lagos, London, Shanghai and many other cities underwater. So, unless the world finally manages to work together to reverse this effect of climate change (ambitious, we know), it looks like we’ll have to start considering the possibility of under-the-sea living.

Luckily, our mortgage experts are always on hand to help you with your housing queries, so compare mortgages and home insurance with us... 

Following the fantastic response to our research into a mortgage on the moon, this time, we’ve researched exactly how much these subaquatic settlements would cost you and found the best spots to build your brand new property. These areas are bound to be in demand,  but don’t worry: once you’ve read this, you’ll be well prepared when the time comes to make the move from Atlanta to Atlantis. Race you to the best reef? 

How far will your money go underwater?

We all knew we’d have to pay for the human contribution to climate change, but we didn’t expect this to be quite so literal. Turns out, it’s not cheap to build an entire home underwater. The simple insulation and double glazing we’ve come to count on when building terrestrial homes simply won’t suffice when submerged 100m underwater - the necessary structural work, water-proofing and air source installation results in some huge property costs.

A living room with sea view

A submarine villa will cost you $1 million

The cheapest investment into underwater ‘seal estate’ will set you back $1,000,000. There are submarine villas for sale in Dubai at this going rate, for those who want to get a head start on the rest of the world. There are 42 villas being built as a part of this development, but if you are a fan of the floor plan and not the locale, you can expect to pay a similar amount when beginning the build at your desired address. Time to set up a sub-aquatic savings account.

Build yourself a floating home for $1.8 million

If you’re after more of a hybrid approach, the design of the ‘Floating Seahorse’ house might appeal more to you. Also being built in this Dubai development, these homes combine the joys of breathing oxygen with all the fun of a glass bottom boat. Only the lower level of this build is submerged, so for those that don’t want to commit to the full underwater lifestyle, you’ll need to have $1,800,000 in the bank to make your dreams a reality. Hot tip: it’s worth spending some extra to make sure you don’t float away. It’s pretty lonely in the middle of the ocean. 

A ‘small’ underwater abode will set you back $4 million

U.S. Submarine Structures LLC has priced up its own creation, the H20ME - a pun we wish we’d thought of first - in a small and large size. Their plan is to build their own sub(marine)urban paradise, and a 1,250 sq ft property there will cost you a cool $4 million. So, if you think this size home will suffice when it’s time to up and move to your newer, soggier neighborhood, this is the probable price tag.

Scale up your aqua accommodation for $12 million

For those of you who like to live a little more lavishly, the H20MEs can also be built at 3,600 sq ft. Depending on your choice of location and luxurious add-ons (a personal jet ski does sound nice), these houses come with an eel-y big price tag: $12 million, as a rough estimate. If you have expensive taste, these houses are the ones to go for. Grab a few high-earning friends and create your very own subaqueous private community of marine mansions. Bever-sea Hills, if you will.

A living room with sofa under the sea

Understand repayments and watch out for loan sharks

The average cost of an underwater abode according to the above properties is $4,700,000. This is a lot as is, but when you consider the interest rates and repayments should you need a loan, the price shoots up. To make sure you are fully aware of the cost involved in this move, here’s some free financial consultansea for you… 

If you take out a loan on the average underwater house price, $4,700,000, and there’s a 4.5% interest rate on it which you pay back over 25 years, you can expect a monthly repayment of $23,511.71. The total repayment after this will be $7,053,514.15 - so before you commit, make sure the financials are figured out. There’s nothing worse than finding yourself in deep water after not planning ahead.

A house underwater with views of a reef

The best locations for underwater living

Once you’ve decided on the perfect hydro-house for you, and started budgeting ASAP, it’s time to decide on where in the world you’ll build it. With 139,668,500 square miles of ocean-covered land at your fingertips - an amount that will only increase as the years pass by, lucky for you - there’s plenty of choice when it comes to deciding where to build your future home. We’ve compiled the information on over 350 dive spots around the world, to calculate which have the best conditions in which to start a new underwater life. After all, we just want your move to go as swimmingly as possible.

Caves make an ideal location for adventurous homeowners

Cenote San Actun is part of the largest underwater cave system in the world, so it presents a great opportunity for an entire community of submarine citizens. Located in Mexico, anyone flooded out of the North American coastal cities won’t have far to travel before they can pop the champagne in their brand new home. There’s a very low current in this cave, so your home can stay structurally sound for many years to come, and the water around you will be 24-25°C, keeping you cosy all year round. Parts of the cave are quite shallow (for now), but there’s a maximum depth of 70m in some parts, so you can build floor after floor without ever reaching the fresh air above. It’s the perfect setting for the most ‘sofishticated’ homes.

Image of underwater caves in Mexico

Reefs in the Philippines would make a colourful location for your new home

Looking for a more tropical location for your new home? Balicasag Island is located in the Philippines and is surrounded by stunning reefs and varied wildlife. Does having a turtle as a neighbour sound good? Yeah, we thought so. The reefs aren’t particularly deep - the deepest part is 42m - but there’s certainly enough space for a nice bungalow. It might be tricky to get the planning permission, considering the island has been declared a marine sanctuary, but it’s nothing a little sweet talk can’t get around.

Considering much of the Philippines will be underwater by 2050 at the current rate, another of its islands being one of the best underwater spots for the future move underwater is only fair. For anyone needing to leave the affected areas, Pamalican Island is a great option for the next stage of your life. There’s a low current, warm water and enough depth to fit at least two floors. Make sure to add lots of fit-for-underwater glass: you can see more than 30m ahead of you in this water. Just because the climate is changing doesn’t mean your love of views has to. 

The Philippines’ own Panglao Island is another of the best spots to build your brand new underwater home. With the same great conditions as the others, this island is surrounded by clear blue water and world-class diving sites - which could soon become your new stomping ground. Your underwater abode will be the envy of all, with its covetable views and surrounded by the most stunning sea life around, that is until the house-building scares it all away. Water you waiting for?

Located in sunny Indonesia, Sondana Beach is also an excellent choice when deciding where to build your new underwater home. There’s a maximum depth here of 80m and a low current, so it’s perfect for any more ambitious architectural plans. In the surrounding area, there’s no lack of marine life, so you can spend your days admiring the native fish species, and your nights reminiscing about when you could leave your house without having to put on a full diving suit.  

N.B. You can get a tan underwater, so ‘seas’ the day and make the most of the Indonesian sun. 

A coral reef with a school of fish

Sinkholes are perfect for lone-wolf living

If you want to live out your days in total silence, and darkness, then a sinkhole might be for you. With depths of up to 100m, there’s plenty of room for your brand new home, albeit with much more opportunity to build upwards than outwards. The Blue Hole in Malta is 15m wide, so you won’t have to do much to chase away any potential neighbours. 

If Malta’s waters aren’t your cup of sea, then Egypt has its own sinkhole that’s bound to be in demand if the en masse move underwater takes place. The average water temperature is 25°C, so it won’t be hard to keep your multi-multi-storied home warm and cosy all year round. 

Both of these locations are well connected to the rest of the ocean, so it’s easy to get to the open water if you ever want to meet up with nearby friends. However, if you want to do this, we’re not sure why you’d choose to live in an isolated sinkhole. 

A diver swimming to the surface of a sinkhole

Image credit

The top 10 locations for underwater living 

Updated 14 October 2021
CountryLocation & Dive TypeCurrentVisability (m)Water Temp(°C)Depth (m)
MexicoCenote Sac Actun - Cave Low current> 30 m24-25 °C2-70 m
PhilippinesBalicasag Island - ReefLow current> 30 m28-30 °C5-42 m
PhilippinesPamilacan Island - ReefLow current> 30 m28-30 °C5-42 m
PhilippinesPanglao Island - Reef Low current> 30 m28-30 °C5-42 m
IndonesiaSondana Beach - ReefLow currentup to 20 m25-29 °C5-80 m
IndonesiaTimur - Wall Some currentup to 30 m25-29 °C5-50 m
MaltaBlue Hole - SinkholeLow currentup to 30 m22-28 °C0-100 m
EgyptBlue Hole - SinkholeLow currentup to 30 m22-8 °C0-100 m
GreeceRemezzo - ReefNo current> 30 m18-27 °C1-45 m
EgyptRas Mohammed - ReefLow currentup to 30 m24-29 °C5-35 m

Is aqua-accommodation the future? 

Dining room with views of a coral reef

While living underwater may sound like the opportunity of a lifetime, there aren’t many of us who could afford the huge costs involved with building something habitable in the ocean. Instead, what we can afford to do is put time and effort into keeping the sea levels as low as possible, so that these underwater homes become just a novelty, not a necessity. 

However, if it did come down to it, above ground etiquette still exists underwater - so don’t forget your manners. If the ocean says hello to you in the morning, the least you can do is wave back.

Whether it’s above ground or below sea level, money.co.uk can help find our best mortgage deal for you. 

Methodology & sources