Every hotel worth its bath salts is claiming to do its bit for the planet. But aside from politely asking guests not to chuck their sodden towels on the floor after every rainfall shower, it’s not always easy to separate the green giants from the greenwashers – especially if you’re looking for truly sustainable luxury hotels in London.

If eco-consciousness is a top priority when booking a luxe stay, start by looking for BREEAM certification. An arm of the Building Research Establishment, this third-party certification assesses the general sustainability and environmental performance of every building within a development, making it a great starting point. Other measures to look out for include food sourcing and waste management, B Corp or Positive Luxury certification, as well as specific procedures for saving and reusing water, electricity, and gas.

From planting over a thousand indoor shrubs and recycling materials on-site, to minimising single-use plastics in bathrooms and bars, these top London hotels are leaning into green with style.

Ham Yard Hotel, Soho

Awarded a BREEAM ‘excellent’ rating at the end of last year, the beautiful and luxurious Ham Yard Hotel was judged to exceed standards by more than 40 per cent. CHP units and solar panels are used to generate electricity, while the team is stringent on separating food waste to be collected by ReFood, after which it is converted into renewable energy, supplying gas to the national grid.

There is also a focus on recycling in-house with all old menus going into making waiters’ notepads. Plus, linens are washed at the on-site Palace Laundry, where the tunnel washer system significantly reduces water usage. Head to the roof terrace garden to see the beehives and vegetable garden, the fruits of which can be enjoyed table-side downstairs. Feel the buzz.

From £618 per night, visit firmdalehotels.com

Treehouse Hotel, Marylebone

This beautiful hidden gem in central Marylebone certainly doesn’t have its head in the clouds when it comes to doing its bit for the environment. Having launched a program with Foodprint Group to replace any single-use items with reusable, recyclable and compostable options, it also offers filtered water in the hallways to reduce single-use plastic bottles, uses only sustainably-sourced linens, and has abandoned the use of single-use printed materials by going totally digital. What’s more, visitors will love the eclectic design of the quirky hotel, peppered with flea market furniture, objects and dining wear throughout the public spaces. Second-hand never looked so good.

From £335 per night, visit treehousehotels.com

1 Hotel Mayfair

With a founding vision across the 1 Hotel group to create an unexpected union of sustainability and luxury, a solid green ethos is at the very core of this beautiful Mayfair hotel, which landed an ‘excellent’ BREEAM rating. Sustainably-sourced and recycled materials have been implemented throughout its refurb, including reclaimed metal floor tiles, one of the largest carbon contributors on any new build.

Blooming living walls and more than a thousand individual plants, shrubs and trees scattered around the unique property are both aesthetically and environmentally pleasing. What’s more, the combined heat and power system produces electricity that will be fed back into London’s utility grid, with the waste heat used to warm the water on-site. Everything from lighting, laundry and linen to water and waste has been considered, with steps to be as sustainable as possible maximised at every turn. Seeing the woods for the trees indeed.

Rooms for £499 per night, visit 1hotels.com

The Lanesborough, Belgravia

Naming themselves the Green Guardians, The Lanesborough’s corporate social responsibility team take their jobs very seriously at this regal and opulent London landmark. Executive Chef Shay Cooper and his team are all about championing regional artisans and using seasonal produce sourced from around the British Isles, from fish and seafood to cheese, as well as the hotel’s in-house dry gin partner, the Hawkridge Distillers.

Only electric and hybrid vehicles are used to chauffeur guests around town in style, while water management is ensured through changing linens every other day, with guests encouraged to reuse their towels. Plus, you won’t find single-use toiletries in any of the fancy bathrooms, which all use large refillable vessels instead. There go the sustainable stocking fillers…

Rooms from £845 per night, visit oetkercollection.com

One Aldwych, Covent Garden

Branding itself as a home for Londoners at heart (wherever they may actually be from), this elegant, independent hotel is certainly setting the standard when it comes to sustainability. With a comprehensive recycling policy with a focus on reducing and reusing, an on-site glass crusher turns old bottles into building materials, while water filtration and bottling is also done in-house to save on single-use plastics. Built to maximise the reduction of utilities, energy, and water, the specialised drainage system EVAC uses 70 per cent less water than an average hotel.

Elsewhere, guests will also feel the benefit of the chlorine-free swimming pool, rooftop beehives and bee-friendly garden to support the health of urban bees, as well as the sourcing of fresh, ethical, sustainable (and obviously delicious) food direct from local suppliers.

From £650 per night, visit onealdwych.com

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