Baking Soda in Laundry

Short answer

• Baking soda in laundry works best as a booster added with your regular detergent, not as a replacement for detergent. It helps neutralize acidic odors and can soften wash water a little, which may help detergent work better.
• For a standard load, use 1/2 cup of baking soda added to the drum with your detergent. Utah State University Extension gives up to 1 cup per load for perspiration odors. Start at 1/2 cup and use more only for a genuinely smelly load.
• Baking soda does not disinfect laundry, does not replace bleach for whitening, and does not guarantee that any particular stain will come out. Do not rely on it for items that need sanitizing.
• Do not mix baking soda and vinegar in the same wash step, and never mix any laundry product with chlorine bleach unless the product label tells you to.
• Always follow the care label on the garment and the manual for your machine. Those instructions override any general guide, including this one.

What Baking Soda Is and Why It Helps With Odor

Baking soda is sodium bicarbonate, a white powder and a mild alkali. In water it forms a solution with a pH of about 8.3. That single fact explains most of what it can and cannot do in a washing machine.

Many laundry odors are acidic: sweat, body odor, sour milk, and the stale smell of a load left damp. An alkali neutralizes acids, turning them into salts that smell less strongly or not at all. Baking soda is therefore an odor neutralizer, not a perfume. It does not cover a smell with a stronger scent; it changes the chemistry of some of the compounds that cause it.

Utah State University Extension states this plainly: baking soda neutralizes acid-based odors in water, and for laundry it advises adding up to a cup per load to eliminate perspiration odors. ARM & HAMMER gives the same core idea, saying that baking soda neutralizes odors by balancing pH levels and softens wash water so detergent can work more effectively. Neither source promises that baking soda cleans clothes on its own, kills germs, or removes every stain. Detergent, water, agitation, and time do the main cleaning work.

Note what baking soda is not. It is not baking powder, which contains an acid ingredient and a starch. It is not washing soda, sodium carbonate, a stronger alkali covered later in this guide. For this guide, the product is plain baking soda: sodium bicarbonate, nothing else added. If the box lists other active ingredients, follow that product label instead.

What Baking Soda Does Well in Laundry

Baking soda earns its place in a few specific situations. Used there, it is cheap, simple, and low risk for most sturdy washable fabrics. Used in every load out of habit, it adds little and can leave residue, so targeted use is best.

First, it freshens smelly loads: gym clothes, work shirts worn on a hot day, pet bedding, dish towels that have sat damp, and towels left too long in the washer. A wash with detergent plus baking soda often smells noticeably fresher, because the baking soda neutralizes some acidic odor compounds that detergent and water alone leave behind.

Second, it can help detergent perform better in hard water. Hard water contains dissolved calcium and magnesium, which react with detergent, forming scum and reducing cleaning power. Baking soda can bind some of those minerals and raise wash water pH slightly. The effect is modest: it is not a full water softener, and very hard water may still need a dedicated softener or a detergent formulated for hard water.

Third, it helps with the general freshness of sturdy items such as cotton towels, sheets, and everyday cotton clothing. Towels benefit in particular, because thick cotton holds odor and takes a long time to dry. A periodic baking soda wash can reset towels that smell stale even when they look clean. This is a freshness benefit, not a whitening claim: baking soda will not bleach yellowed towels white or remove a set stain.

What Baking Soda Does Not Do

Baking soda does not disinfect. Neither ARM & HAMMER nor Utah State University Extension describes it as a disinfectant, and sodium bicarbonate does not appear as a registered disinfectant active ingredient on the United States Environmental Protection Agency’s List Q. If an item needs to be sanitized, such as bedding used by someone who is sick, baking soda alone is not enough. Use a product labeled as a sanitizer or disinfectant for laundry, exactly as its label directs. A load that smells fresh is not necessarily sanitized.

Baking soda does not replace detergent. Detergent contains surfactants, the ingredients that lift soil and oil from fabric and hold them in the wash water so they rinse away. Baking soda contains none. A load washed in baking soda and water alone will smell somewhat better but will not be properly cleaned. ARM & HAMMER positions baking soda as a booster used with detergent, pairing 1/2 cup of baking soda with regular liquid laundry detergent. Always use the normal amount of detergent for the load size and soil level.

Baking soda does not bleach whites. It may help whites look a little brighter by improving detergent performance and reducing the mineral film that makes fabric look dingy, but that is a modest, indirect effect. It is not oxygen bleach or chlorine bleach and will not whiten yellowed or grayed fabric on its own. For whitening, use an oxygen bleach product labeled safe for the fabric, following its label.

Baking soda does not guarantee stain removal. A paste of baking soda and water can help with some fresh, mildly acidic marks, but grease, blood, ink, dye, rust, and set-in stains each need their own treatment, and many will not come out fully. Treat stains promptly, test any pretreatment on a hidden area first, and check the stain before drying, because dryer heat can set a stain that washing did not remove. Baking soda also does not soften fabric like fabric softener, prevent static cling, or by itself clean a smelly washing machine, which usually needs its door seal and dispenser drawer cleaned.

How Much Baking Soda to Use

Start with 1/2 cup per standard load. ARM & HAMMER laundry guidance uses 1/2 cup added to the washer with detergent, plus another 1/2 cup in the rinse cycle for extra freshness. Utah State University Extension gives a ceiling of up to 1 cup per load for perspiration odors. The practical range is therefore 1/2 cup for a routine load and up to 1 cup for a large or very smelly load.

For a small load, or for a high efficiency machine that uses much less water, use about 1/4 cup. The same 1/2 cup is more concentrated in less water, and excess powder is more likely to leave residue. Check your machine manual first: some manufacturers give specific guidance on adding powders, and the manual wins over any general amount in this guide.

Do not keep increasing the dose: doubling it does not double odor removal. Once the wash water is mildly alkaline, extra powder mostly sits undissolved or rinses out unused, and repeated overdosing can leave chalky residue on dark fabrics and in the machine. If 1 cup in a full, smelly load does not freshen the items, the problem is probably not the dose. The items may need a soak, a different treatment, or more thorough drying. Measure the baking soda rather than pouring from the box.

| Load type | Baking soda amount | Notes | | Standard top loader, routine freshening | 1/2 cup | Add with detergent to the drum | | Large or very smelly load | Up to 1 cup | Utah State University Extension ceiling for perspiration odors | | Small load | 1/4 cup | Scale down with load size | | High efficiency machine | 1/4 cup to 1/2 cup | Start low, check the manual, watch for residue | | Soak before washing | 1/2 cup to 1 cup in a basin of warm water | Soak 30 minutes to a few hours, then wash as usual | | Paste pretreatment | A few tablespoons mixed with a little water | Test on a hidden area first, then wash as usual |

How to Add Baking Soda to a Load

For a top loader, sprinkle the measured baking soda directly into the drum before adding clothes, or dissolve it in warm water first and pour it in as the machine fills. Add your regular detergent as usual. Adding the powder before the clothes helps it dissolve and spread evenly.

For a front loader, dissolve the baking soda in a cup or two of warm water first, then pour the solution into the drum before adding clothes. Do not pack dry powder into the detergent dispenser unless your machine manual specifically tells you to, because powder can clump in a dispenser drawer and may not reach the load at all.

Wash on warm water when the care label allows it. Warm water dissolves baking soda more completely than cold water, so dissolving the powder in warm water first matters more in a cold wash. Always respect the care label: if an item calls for cold water, use cold water and dissolve the powder first.

Add an extra rinse if your machine offers one and you used baking soda on dark clothes or in a high efficiency machine. Dry items completely before folding or storing them: damp fabric in a drawer or hamper will develop a musty smell no matter what was added to the wash.

Step by Step: A Standard Baking Soda Wash

This routine suits a smelly but otherwise ordinary load, such as gym clothes, work clothes, or towels.

1. Sort the load as usual and check the care labels. Keep wool, silk, and items labeled dry clean only out of this load.
2. Measure 1/2 cup of baking soda for a standard load, or 1/4 cup for a small or high efficiency load.
3. For a top loader, sprinkle the baking soda into the empty drum. For a front loader, dissolve it in warm water first and pour it into the drum.
4. Add clothes and your regular detergent in the normal amount for the load size and soil level.
5. Select a warm wash cycle if the care labels allow it, or the warmest setting the labels permit. Add an extra rinse if the machine offers one.
6. When the cycle ends, remove the load promptly and dry it completely, following the care labels. Check dark items for white residue before folding.
7. If odor remains after a full wash and complete drying, try the soak method below rather than repeating the same wash with more powder.

For extra freshness, ARM & HAMMER suggests another 1/2 cup of baking soda in the rinse cycle. That is optional. Try the single addition first, and watch for residue on dark fabrics.

Soaking and Pretreating

Some loads need more contact time than a single wash cycle gives. For forgotten towels that sat damp, pet bedding, sports gear, and work clothes with ground-in sweat odor, dissolve 1/2 cup to 1 cup of baking soda in a basin of warm water, using enough water to cover the items. Let them soak for 30 minutes to a few hours. Very smelly sturdy items such as cotton towels can soak for several hours, but do not soak items overnight as a habit, and do not soak wool, silk, leather, or items with a care label that forbids soaking. After soaking, run a normal wash with detergent. Do not skip the wash: the soak loosens odor, but the wash removes the soil. If a soak plus a full wash does not freshen an item, the odor may be trapped in a layer washing cannot reach, and replacing the item may be wiser than repeating stronger treatments.

A paste of baking soda and water can help with some fresh surface marks, such as sweat marks around collars and underarms. Mix a few tablespoons of baking soda with just enough water to form a thick paste, spread a thin layer over the mark, let it sit for 15 to 30 minutes, then wash as usual with detergent. Check the mark before drying. Test any paste on a hidden area first: as a paste, baking soda is mildly abrasive, and hard rubbing can wear fabric or lighten dye. Apply it gently, and skip the paste on delicate fabrics, silk, wool, and items with special finishes.

High Efficiency Machines and Fabrics to Skip

High efficiency washers use much less water than older machines, so the powder has less water to dissolve in and to rinse out. That is why the starting amount is lower, about 1/4 cup to 1/2 cup, and why dissolving the powder in warm water first matters more. Check the machine manual before adding any powder. If white residue appears, reduce the amount, dissolve it first, and add an extra rinse. If residue persists, stop using baking soda in that machine. A musty front loader is usually a maintenance problem, moisture and residue in the door seal and dispenser, not a missing additive. Wipe the seal, clean the drawer, leave the door ajar between loads, and run the cleaning cycle your manual recommends.

Wool and silk should not be treated with baking soda. Both are protein fibers, and alkaline conditions can damage them, causing felting in wool and weakening and yellowing in silk. Wash them with a detergent made for delicates. Leather, suede, items labeled dry clean only, items with waterproof coatings, and items with foam padding that cannot be fully rinsed should never go through a baking soda wash. Delicate, beaded, and vintage garments deserve the gentle cycle the label calls for, with baking soda skipped unless tested on a similar, less valued item first.

Dark clothes need a residue check. Baking soda does not bleach color, but undissolved powder can leave white marks on dark fabric that look like fading. Dissolve the powder first, use the lower end of the dose range, and add an extra rinse for dark loads. Cloth diapers deserve caution too: baking soda can help with odor, but it does not sanitize. Follow the diaper manufacturer instructions for sanitizing, and rinse thoroughly, since residue against skin can irritate sensitive skin.

Baking Soda and Vinegar, and Baking Soda Versus Washing Soda

One of the most repeated laundry tips is to add baking soda and vinegar together for extra cleaning power. The chemistry says otherwise. Baking soda is a base and vinegar is an acid. When they meet, they react to form water, carbon dioxide gas, and sodium acetate, a weak salt. The fizz looks active, but it is the sound of the two ingredients canceling each other out. Once the reaction finishes, much of the acid and much of the base is gone, and the leftover liquid cleans less effectively than either ingredient used on its own.

That does not mean vinegar has no place in laundry. The two should be used at different stages, if both are used at all: baking soda with detergent in the main wash, and vinegar in a separate rinse cycle, where it can help dissolve alkaline residue.

This distinction also matters for oven cleaning, where the same pair is often confused. Our companion guide to cleaning an oven with vinegar and baking soda uses the two in sequence: a baking soda paste softens baked-on soil first, and vinegar is used afterward only to loosen leftover paste residue. The laundry rule is the same: sequence, not a premixed combination. That method is covered in full in our companion oven-cleaning guide, rather than repeated here.

Never mix vinegar, baking soda, or any laundry additive with chlorine bleach. Mixing an acid such as vinegar with bleach can create harmful gases. Use bleach, if you use it at all, on its own, exactly as its label directs, and never combine it with another cleaner in the same wash.

Baking soda and washing soda look alike, but they are different compounds. Baking soda is sodium bicarbonate, a mild alkali with a pH of about 8.3. Washing soda is sodium carbonate, a stronger alkali with a pH around 11. Washing soda cuts grease more aggressively and softens water more strongly, but it is harsher on fabrics and skin. Do not substitute one for the other by amount. If a recipe calls for washing soda, follow its own label and safety guidance, wear gloves, and keep it away from children and pets.

Troubleshooting and When to Skip Baking Soda

White residue on dark clothes usually means undissolved powder or too large a dose. Dissolve the baking soda in warm water before adding it, reduce the amount to 1/4 cup, and add an extra rinse. Rewash affected items with detergent and no baking soda to remove the residue.

Odor that returns after washing usually points to incomplete drying, damp storage, or a machine that needs cleaning, rather than a missing additive. Dry items fully, store them dry, wipe the door seal, and clean the dispenser drawer. Stiff towels often mean too much product, too little rinsing, or very hard water: use less baking soda and add an extra rinse. Colors that look duller after repeated baking soda washes may show alkaline exposure, hard water minerals, or simply age and wash wear. Wash darks in cold water, turn items inside out, and skip baking soda where color preservation matters most.

Baking soda is the wrong tool in several common situations. For disinfection, use a product labeled for that purpose and follow its label exactly. For whitening, use an oxygen bleach product labeled safe for the fabric. For grease stains, use a pretreatment made for grease, applied promptly. For protein stains such as blood, milk, or egg, use cold water and an enzyme product, because hot water can set protein stains. For a load that already smells fresh with detergent alone, skip baking soda. For a machine whose manual says it should not receive loose powders, skip it entirely.

Cost, Storage, and a Realistic Verdict

Baking soda is inexpensive. A box costs little, and 1/2 cup per load means a standard box covers only a few loads, so buying the larger bag made for laundry use is more practical if you use it regularly. Keep the laundry supply separate from the baking supply. Store it dry with the box or bag closed; moisture causes clumping, and clumps dissolve poorly and leave residue. Replace a box that has hardened into a solid block. Keep it away from children and pets, and avoid breathing in a cloud of powder when pouring. It is a mild eye irritant in powder form; if powder gets in the eyes, rinse with water.

Baking soda in laundry deserves its reputation, but only within its limits. It neutralizes some acidic odors, gives detergent a small assist in hard water, and freshens sturdy items such as towels and gym clothes at very low cost. It does not clean on its own, does not disinfect, does not bleach, and does not guarantee stain removal. Used at 1/2 cup per standard load with detergent, dissolved first for front loaders and high efficiency machines, and saved for loads that actually need freshening, it is a sensible addition to a routine. The best test is simple: wash a smelly load with detergent plus 1/2 cup of baking soda, dry it completely, and smell it the next day. If it is fresher than the same load washed with detergent alone, it has earned a place in your routine.

Frequently Asked Questions

Can I use baking soda in laundry instead of detergent?

No. Baking soda has no surfactants, so it cannot lift and carry away soil and oil the way detergent does. Use it with your regular detergent, not instead of it. A load washed in baking soda alone will smell somewhat better but will not be properly cleaned.

How much baking soda should I put in laundry?

Use 1/2 cup for a standard load, up to 1 cup for a large or very smelly load, and about 1/4 cup for a small load or a high efficiency machine. Utah State University Extension gives up to 1 cup per load for perspiration odors; ARM & HAMMER guidance uses 1/2 cup with detergent.

Can I put baking soda in a high efficiency washer?

Yes, with care. Dissolve it in warm water first, use the lower end of the dose range, and check your machine manual. Add an extra rinse if residue appears. If residue persists, stop using it in that machine.

Will baking soda damage my washing machine?

At normal amounts, baking soda is not known to damage a washing machine, but excess powder can leave residue in dispensers, seals, and drums. Dissolving it first, using the recommended amount, and cleaning the machine as the manual directs will keep residue from building up.

Does baking soda whiten white clothes?

Not in the way bleach does. It may help whites look a little brighter by improving detergent performance and reducing mineral film, but it will not bleach yellowed or grayed fabric white. For whitening, use an oxygen bleach product labeled safe for the fabric.

Does baking soda remove stains?

Sometimes it helps with fresh, mild marks as a paste pretreatment, but it does not guarantee stain removal. Grease, ink, dye, rust, and set-in stains need treatments suited to their type, and some stains are permanent. Check any stain before drying, because dryer heat can set it.

Can I mix baking soda and vinegar in laundry?

Not in the same wash step. The acid and the base react and cancel much of each other out, leaving water, carbon dioxide gas, and a weak salt. If you want to use both, use them at different stages, for example baking soda with detergent in the wash and vinegar in a separate rinse cycle, and never mix either with chlorine bleach.

Is baking soda safe for colors and dark clothes?

Generally yes, but undissolved powder can leave white marks on dark fabric. Dissolve the powder first, use a smaller dose, and add an extra rinse for dark loads. Wash darks in cold water and turn items inside out to protect color.

Can I use baking soda on wool or silk?

No. Wool and silk are protein fibers that alkaline conditions can damage. Use a detergent made for delicates and follow the care label, and skip baking soda for those loads.

Does baking soda disinfect laundry?

No. Baking soda is not presented as a disinfectant, and it should not be relied on to sanitize items. For items that need sanitizing, use a product labeled as a sanitizer or disinfectant for laundry, exactly as its label directs.

Why do my clothes still smell after washing with baking soda?

The most common causes are incomplete drying, damp storage, a dirty machine seal or dispenser, or an odor trapped in a layer washing cannot reach. Dry items completely, clean the machine as the manual directs, and try a soak for stubborn items. If odor persists after a soak and a full wash, the item may need replacing.

Is baking soda the same as washing soda?

No. Baking soda is sodium bicarbonate, a mild alkali. Washing soda is sodium carbonate, a stronger alkali that cuts grease more aggressively but is harsher on fabrics and skin. Do not swap one for the other at the same amount.

How do I freshen towels that smell musty?

Wash them with detergent plus 1/2 cup of baking soda on a warm cycle the care label allows, add an extra rinse, and dry them completely. For towels that sat damp, soak them first in warm water with 1/2 cup to 1 cup of baking soda, then wash as usual. If the smell comes from the machine, clean the seal and dispenser and leave the door ajar between loads.

Sources & references

• Utah State University Extension, "Greener Cleaners." Opened and read 28 Oct 2026. States that baking soda neutralizes acid-based odors in water and adsorbs odors from the air, and that for laundry, up to a cup per load may be added to eliminate perspiration odors and neutralize the smell of chemicals.
• ARM & HAMMER, "How to Get Laundry Extra Clean and Fresh with Baking Soda." Opened and read 28 Oct 2026. States that baking soda neutralizes odors by balancing pH levels and softens wash water so detergent can work more effectively, and gives a method of 1/2 cup of baking soda in the washer with detergent, with another 1/2 cup in the rinse cycle for extra freshness.
• ARM & HAMMER, "Baking Soda Laundry Booster" recipe. Opened and read 28 Oct 2026. Directs adding 1/2 cup of baking soda into the washer with regular liquid laundry detergent and washing as usual.
• ARM & HAMMER, Product FAQs, Baking Soda section. Opened and read 28 Oct 2026. States that baking soda is made of 100 percent sodium bicarbonate, while Super Washing Soda is made of 100 percent sodium carbonate, and that the two are not the same product.
• United States Environmental Protection Agency, "Disinfectants for Emerging Viral Pathogens (EVPs): List Q." Opened and read 28 Oct 2026. Lists registered disinfectant products by active ingredient and registration number; sodium bicarbonate does not appear as a registered disinfectant active ingredient for laundry use, which supports the statement in this article that baking soda is not presented as a disinfectant.