Clean Sunbrella cushions with mild soap, water, and a soft brush — never bleach or pressure washers
Sunbrella fabric is acrylic-based and resists mildew and fading better than cotton, but it still needs regular cleaning to stay looking new. The safest method is a mixture of lukewarm water and mild dish soap applied with a soft-bristled brush, followed by a thorough rinse. Avoid bleach, vinegar, and pressure washers, which can break down the fabric's protective coating and cause permanent damage.
How often you clean depends on where your cushions sit. Cushions under a covered patio need cleaning once or twice a year. Cushions in full sun or near trees, where pollen and bird droppings land, benefit from a quick rinse every month and a deeper clean every three months.
Key Takeaways
- Mix one-quarter cup of mild dish soap with one gallon of lukewarm water and scrub with a soft brush, then rinse thoroughly with clean water.
- Never use bleach, vinegar, hydrogen peroxide, or pressure washers on Sunbrella fabric, as these damage the acrylic coating.
- For mildew or stubborn stains, a commercial Sunbrella cleaner designed for the fabric works better than household products and costs between $10 and $20 per bottle.
- Dry cushions completely in sunlight or with a towel before storing them, because trapped moisture can cause mildew to return.
- Sunbrella fabric is colorfast and fade-resistant, so regular cleaning is mainly about removing dirt and preventing mildew buildup.
The basic cleaning method for everyday dirt and dust
Start by removing loose dirt. Take the cushions outside and tap them against each other or a hard surface to dislodge dust and debris. If they are still on the furniture, use a handheld vacuum with an upholstery attachment to remove surface dust without pressing hard.
Mix one-quarter cup of mild dish soap — Dawn, Seventh Generation, or an equivalent — with one gallon of lukewarm water in a bucket. Dip a soft-bristled brush (a natural horsehair brush or a soft nylon deck brush works well) into the solution and scrub the cushion in circular motions, paying extra attention to seams and piping where dirt collects. Work on one section at a time, about two feet square, so the soap does not dry on the fabric.
Rinse each section when ready with clean water from a garden hose on low pressure or a watering can. Do not use a pressure washer, even on the lowest setting — the force can push water into the cushion's core and weaken the stitching. Repeat the soap-and-rinse cycle until the water runs clear and no soap residue remains.
Removing mildew and stubborn stains
If your cushions have developed a gray or black mottled appearance, that is mildew, not permanent staining. Mildew on Sunbrella usually comes off with the basic soap-and-water method, but if it persists, a commercial Sunbrella cleaner is the next step. Brands like Sunbrella Cleaner or Star brite Mildew Stain Remover are formulated to work on acrylic without damaging the fabric. Follow the product instructions exactly — most require dilution and a waiting period of 10 to 15 minutes before scrubbing.
For bird droppings, tree sap, or food stains, rinse the spot with water first, then explore the soap solution and let it sit for five minutes before scrubbing. Sunbrella's acrylic fibers do not absorb liquids the way cotton does, so stains usually sit on the surface and come off more easily than you might expect. If a stain remains after one cleaning, repeat the process rather than scrubbing harder, which can fray the fibers.
Do not use bleach, even diluted. Bleach breaks down the acrylic coating that makes Sunbrella water-resistant and fade-resistant. Vinegar and hydrogen peroxide have the same effect. These products may lighten a stain temporarily, but they will permanently weaken the fabric.
Drying and storage to prevent mildew from returning
After rinsing, squeeze out excess water gently with your hands or a clean towel. Do not wring the cushions. Lay them flat in direct sunlight or stand them upright against a wall in a well-ventilated area. Sunlight is the best natural mildew preventative, so if weather permits, leave the cushions in the sun for at least two hours after cleaning.
If you are storing cushions for winter or an extended period, make sure they are completely dry first. Trapped moisture inside the cushion core is the main cause of mildew returning. Store them in a cool, dry place — a garage, shed, or storage bin with ventilation holes. Do not seal them in an airtight container. If you use a storage bag, choose one with mesh panels that allow air to circulate.
When to use commercial Sunbrella cleaner instead of soap and water
Commercial cleaners designed for Sunbrella are worth the cost if you have heavy mildew, multiple stains, or cushions that are difficult to rinse thoroughly. These products are concentrated and require less water, which is useful if you are cleaning cushions that are still on the furniture or in a location where rinsing is inconvenient.
Sunbrella Cleaner, made by the fabric manufacturer, costs around $15 to $20 per bottle and covers multiple cushions. Star brite Mildew Stain Remover is a similar price and works on both Sunbrella and other outdoor fabrics. Both are available online and at home improvement stores. Read the label to confirm the product is safe for your specific cushion color — some cleaners are not recommended for very light or very dark fabrics.
What not to do: common mistakes that damage Sunbrella
Pressure washers are the most common culprit. Even on the gentlest setting, the concentrated stream of water can force moisture into the cushion's interior, damage stitching, and weaken the fabric's water-resistant coating. A garden hose on low pressure or a watering can is always safer.
Scrubbing too hard is the second mistake. Sunbrella is durable, but aggressive scrubbing can fray the fibers and create a fuzzy, worn appearance. Let the soap do the work — a gentle circular motion with a soft brush removes dirt without damaging the weave.
Storing damp cushions is the third. Even if a cushion feels dry to the touch, moisture trapped inside can cause mildew to develop within days. Always allow at least two hours of air drying or sunlight before storing.
How often to clean based on your patio's location
Cushions under a covered patio or overhang need the least maintenance. Clean them once in spring and once in fall, or whenever you notice visible dirt or dust. These cushions are protected from rain and direct sun, so mildew is less likely to develop.
Cushions in partial sun or shade, away from trees, benefit from cleaning every three to four months. This schedule prevents dust and pollen from building up and keeps mildew from taking hold.
Cushions in full sun near trees or in humid climates should be rinsed monthly with plain water and cleaned thoroughly every two to three months. Pollen, bird droppings, and sap accumulate faster in these locations, and humidity speeds up mildew growth. A quick rinse takes 10 minutes and extends the time between deep cleanings.
Frequently Asked Questions
Can I use a washing machine or hose down the cushions in the rain?
Do not use a washing machine — the agitation and spin cycle will damage the fabric and stitching. A gentle rinse with a garden hose on low pressure is fine, but do not rely on rain to clean the cushions. Rain water often contains dirt and pollen that settle on the fabric rather than rinsing it away.
What if my cushions have a strong smell after cleaning?
A musty smell usually means moisture is trapped inside the cushion core. Lay the cushions in direct sunlight for several hours or stand them upright in a well-ventilated area. If the smell persists after drying, the cushion may have developed mildew inside, and you may need to replace it.
Is it safe to use a steam cleaner on Sunbrella?
No. Steam cleaners force hot water deep into the fabric and can damage the acrylic coating and stitching. Stick to cool or lukewarm water and a soft brush.
Do I need to treat Sunbrella cushions with a protectant after cleaning?
Sunbrella fabric comes pre-treated with a water-resistant and stain-resistant coating from the manufacturer. You do not need to reapply a protectant. Regular cleaning and proper drying are enough to keep the fabric in good condition.
Can I clean Sunbrella cushions with an outdoor furniture cleaner?
Check the label first. Many all-purpose outdoor cleaners are safe for Sunbrella, but some contain bleach or harsh chemicals that damage acrylic. If the label does not specifically mention acrylic or Sunbrella, use mild dish soap and water instead.