How to Clean with Bicarbonate of Soda: The Complete Guide (UK)

Bicarbonate of soda is one of the best value things you can keep under the sink. A big tub costs very little, it lasts for ages, and it quietly handles a surprising number of jobs around the house: scouring a sink, taking the smell out of a bin, freshening a carpet, lifting tea stains from a mug. It is worth knowing exactly what it does well, though, because it also gets over-sold. It is mild, not miraculous, and one of the most repeated tips about it, mixing it with vinegar, is mostly a bit of theatre. This guide sorts the genuinely useful from the folklore, in British measures and with the naming confusion cleared up first.

Quick note on names. In the UK we call it bicarbonate of soda, or bicarb for short. It is exactly the same product that is known as baking soda in the US, so if a recipe or video says baking soda, that is what you already have. The important distinction is not British versus American, it is bicarb versus baking powder, and versus soda crystals, which is where people actually go wrong. We will clear that up below.

What bicarbonate of soda actually is, and why it works

Bicarbonate of soda is a single, simple chemical: sodium bicarbonate. It is a fine white powder, the very same one used in baking, and it earns its place in the cleaning cupboard in three ways.

First, it is a mild alkali. That means it helps to loosen and break down greasy, acidic dirt, the sort of everyday film that builds up on worktops and cookers, without being harsh. Second, the powder is a gentle abrasive: the fine grains give a bit of scouring bite, enough to shift stuck-on marks, but soft enough that they will not scratch most surfaces the way a harsh scouring powder can. Third, and this is where it really shines, it is an excellent odour absorber. Rather than masking smells with perfume, bicarb genuinely takes the edge off them, which is why it is the classic trick for fridges, bins and trainers.

Put those three properties together and you have a cheap all-rounder for light, everyday cleaning and freshening. What it is not is powerful. It will not strip baked-on oven grease on its own, and, importantly, it is not a disinfectant. It makes things cleaner and fresher, but "fresh" is not the same as "sanitised", so it is the wrong tool if killing germs is the point of the job.

Bicarb versus baking powder versus soda crystals

This is the bit that trips everyone up, so it is worth being precise. All three are white powders sold in the baking or cleaning aisle, and they are not the same.

	Bicarbonate of soda	Baking powder	Soda crystals
Chemical	Sodium bicarbonate (pure)	Bicarb plus a dry acid plus starch filler	Sodium carbonate (washing soda)
Strength	Mild alkali	Mild, but diluted by filler	Much stronger alkali
Best for	Gentle scouring, deodorising, light grease	Baking cakes, not cleaning	Heavy grease, degreasing, tough grime
Handling	Fine with bare hands	Fine with bare hands	Wear gloves; keep off aluminium and lacquer

Here is the plain-English version, because the difference is what matters.

Baking powder is not a cleaning product. It is bicarbonate of soda that has been pre-mixed with a dry acid (usually cream of tartar) and a starch, so that it fizzes by itself the moment it gets wet in a cake mix. For cleaning that blend does you no favours: you are paying for filler, the powder is diluted, and the built-in acid adds nothing to the scrubbing. If a cleaning tip says bicarb or bicarbonate of soda, use plain bicarb, not the baking powder tub.

Soda crystals are the stronger relative. They are sodium carbonate, chemically a cousin of sodium bicarbonate but a considerably stronger alkali. That makes them the go-to for heavy jobs bicarb cannot manage on its own: degreasing, shifting baked-on grime, reviving greasy cloths and cutting through the grease in a slow-draining kitchen sink. The trade-off is that they are harsh enough to irritate skin, so you wear gloves, and they can damage aluminium and lacquered or varnished surfaces, so you keep them off those. If a job needs real muscle, that is a soda crystals job, and we cover them fully on the dedicated soda crystals page.

A room-by-room list of jobs bicarb is genuinely good at

Here is where bicarbonate of soda earns its keep, grouped by what it does.

Gentle scouring

• Sinks, baths and basins. Sprinkle bicarb onto a damp cloth or straight onto the surface, scrub in circles, then rinse. It lifts marks and grime and leaves a light shine without the scratchy harshness of some scouring powders. Good on stainless steel and enamel.
• Hobs and cooker tops. For everyday splashes (not heavy baked-on grease), a damp cloth dipped in bicarb, or a paste left on for a few minutes, will cut through the film. For genuinely burnt-on grease you will want a proper degreaser or soda crystals.
• Mugs and teapots. Tea and coffee leave brown tannin stains inside mugs. A teaspoon of bicarb on a damp cloth, or a paste left to sit for ten minutes, rubs them away easily. It works on stained flasks and teapots too.

Deodorising

• The fridge. An open small pot or saucer of bicarb on a shelf quietly absorbs food odours. Give it a stir now and then and replace it every month or so.
• The bin. A tablespoon of bicarb in the bottom of the bin, under the liner, takes the edge off the smell. Do the same after washing the bin out.
• Carpets and rugs. For a musty or doggy-smelling carpet, scatter a light, even layer of bicarb, leave it for fifteen minutes to a few hours, then hoover it up thoroughly. It absorbs trapped odours as it sits. Always test a small hidden patch first, and hoover it all up so none is left ground in.
• Mattresses and sofas. The same trick freshens a mattress: sieve a thin layer over it, leave it an hour or more, then vacuum it off completely.
• Shoes and trainers. A teaspoon of bicarb tipped into each shoe overnight absorbs the smell. Tap it out (or hoover it) in the morning.

Light grease and general cleaning as a paste

A stiff bicarb paste is the workhorse. Mix roughly three parts bicarb to one part water into a spreadable paste, smear it onto the mark, give it a few minutes, then scrub and rinse. It handles greasy fingermarks, tide-marks in the bath, grimy tile grout, the inside of a microwave and scuffs on paintwork. It is gentle enough for most surfaces but always test somewhere hidden first, and go easy on soft or polished finishes.

Silver

For lightly tarnished silver, a soft bicarb paste on a cloth, rubbed gently and then buffed off, can bring back some shine. Keep it gentle and off any delicate plating or gemstones, and do not scrub hard, as even a mild abrasive can mark soft metal over time.

How to make and use a bicarbonate of soda cleaning paste

1. 1

   Mix the paste

   In a small bowl, stir together about 3 tablespoons of bicarbonate of soda with roughly 1 tablespoon of water. Aim for a thick, spreadable paste, like toothpaste. Add a little more bicarb or water to get the consistency right.

2. 2

   Test first

   Dab a little on a hidden area of the surface and check it does not dull or scratch it. Skip this on soft, polished, waxed or lacquered finishes, and on natural stone.

3. 3

   Apply and wait

   Spread the paste over the mark or grimy area and leave it for 5 to 15 minutes so the mild alkali can loosen the dirt.

4. 4

   Scrub gently

   Work it with a damp cloth, sponge or soft brush, using small circles. Let the fine grains do the scouring rather than pressing hard.

5. 5

   Rinse and dry

   Wipe away all the residue with clean water and dry with a cloth. On food-contact surfaces, rinse well so no powder is left behind.

Freshening a slow or smelly drain

Bicarb is handy for keeping a kitchen or bathroom drain fresh, and it is the one place the bicarb-and-vinegar combination has a small, honest role, as a mechanical flush rather than a chemical miracle (more on that below). Note this freshens and helps shift light grease and gunge; it will not clear a solid blockage, which needs a plunger, a drain snake or a plumber.

Freshen a drain with bicarb (and an optional vinegar flush)

1. 1

   Clear and warm the drain

   Remove any visible debris from the plughole. Boil a kettle.

2. 2

   Add the bicarb

   Tip about 3 tablespoons of bicarbonate of soda directly down the plughole so it sits in the drain.

3. 3

   Optional vinegar flush

   If you like, pour in around 100 ml of white vinegar. It will fizz. This is a gentle mechanical agitation, not a powerful cleaner, so do not expect it to dissolve a blockage. Never do this in a sealed or capped pipe or bottle, only in an open drain.

4. 4

   Leave briefly, then flush

   Leave it for a few minutes, then pour a kettle of hot (not necessarily boiling, to protect some pipes and seals) water down to flush everything through.

5. 5

   For grease, use soda crystals instead

   If the drain is slow with built-up grease, a cup of soda crystals followed by hot water is far more effective than bicarb for that particular job.

The oven

Bicarb is a popular, low-fume way to tackle a moderately dirty oven. Make a thicker paste (bicarb and a little water), spread it over the greasy interior surfaces, avoiding the heating elements and any fan, and leave it for several hours or overnight. The paste softens the grease so you can wipe and scrub it away, then rinse. It is gentler and less smelly than caustic oven cleaners, but be realistic: for heavy, carbonised grease it takes elbow grease and repeat goes, and a dedicated oven product or soda crystals soak for the racks will do more.

The bicarb-and-vinegar myth, explained honestly

You will see this everywhere: tip bicarbonate of soda and vinegar together, watch the dramatic fizz, and marvel at your powerful natural cleaner. It is one of the most repeated cleaning tips going, and it is largely wrong.

Here is the chemistry, kept simple. Bicarbonate of soda is an alkali (a base) and vinegar is an acid. When an acid and a base meet, they neutralise each other. So when you combine bicarb and vinegar, they react to produce carbon dioxide gas (that is the fizz), water, and a small amount of dissolved salt (sodium acetate). In other words, the impressive bubbling is the sound of both your cleaning ingredients cancelling each other out. What is left in the bowl is mostly weak, salty water.

It gets starker when you look at the amounts. Analyses of typical recipe ratios, like the ones in viral oven-cleaning videos, show that after the fizzing dies down the great majority of the bicarbonate of soda is still sitting there unreacted, having done nothing except make bubbles. So even the fans of the mix are mostly cleaning with plain bicarb and a lot of scrubbing, plus a splash of salty water, not with some souped-up super-cleaner.

The practical takeaway is not "these are bad ingredients". Both are genuinely useful. It is that they are useful for different jobs, and mixing them into one bottle wastes both. Use bicarbonate of soda for gentle scouring and deodorising, as above. Use white vinegar for the acidic jobs it is great at, such as descaling a kettle, cutting limescale off taps and shower screens, and cleaning glass, and there is a full guide to that on our cleaning with white vinegar page. Keep them in separate bottles, and reach for whichever one suits the task.

The honest limits

Bicarbonate of soda is a genuinely useful, cheap, gentle cleaner, and it deserves its place under the sink. But keeping your expectations right is what stops it disappointing you.

• It is mild, not powerful. It is a light-duty scourer and deodoriser. For heavy grease, baked-on grime and tough degreasing, soda crystals or a dedicated product will do far more.
• It is not a disinfectant. It freshens and cleans, but it does not sanitise. Use a proper disinfectant where killing germs matters.
• It is an abrasive, so test first. Gentle as it is, it can still dull very soft, polished, waxed or lacquered finishes, and it is best kept off natural stone. A quick test on a hidden spot saves regret.
• Do not overthink it. Half the internet's bicarb "hacks" are just bicarb doing its ordinary job, dressed up. Scour, deodorise, paste. That is what it is for, and it does it well.