Every September, when the mornings start to feel a little cooler here in the Midwest, I get the urge to deep-clean the spots I ignored all summer. Window sills are one of those sneaky places in my house. They collect dead bugs, dust, pollen, little flecks of dirt from screens, and somehow even sticky mystery spots. This time, instead of reaching for my usual all-purpose spray, I decided to try something people have talked about for years: wiping my window sills with original brown Listerine every day for 7 days and seeing what really happened.

I used the old-fashioned amber-colored kind, not the minty clear versions, and I kept the experiment as consistent as I could. I cleaned the same interior window sills once a day for a full week in September, using the same cloths, about the same amount of product, and roughly the same cleaning routine. Some of the results were better than I expected, a few were underwhelming, and one or two things made me decide this is more of a sometimes trick than a forever habit. Here’s exactly how I did it and what I noticed day by day.

1. Why I picked window sills in September

September is prime “reset the house” month for me. The windows have usually been open at least part of August, so by early fall the sills are dusty and gritty. We also tend to get more spiders and little bugs trying to tuck themselves close to the house once the temperature starts dipping at night. My theory was simple: if original brown Listerine has a strong scent and contains alcohol and essential oils, maybe it would help freshen, cut grime, and possibly discourage some insect activity around the sill area.

I tested 5 interior window sills: 2 in the kitchen, 1 in the dining room, 1 in our mudroom, and 1 in the guest bedroom. Each sill was painted wood with a semi-gloss finish. The widths ranged from about 3 1/2 inches to 5 inches deep, and each one was between 28 and 40 inches wide. I chose indoor sills only because I wanted a controlled test without rain, direct outdoor dirt, or changing weather washing the product away.

2. What I used each day

My supplies were basic: original brown Listerine, a small bowl, microfiber cloths, cotton swabs for corners, and paper towels. I poured about 2 tablespoons of Listerine into the bowl for each cleaning session. That was enough to lightly dampen a cloth and do all 5 sills without soaking them.

I did not spray it directly onto the painted wood. Instead, I dampened the cloth so the surface was wet but not dripping. On average, each sill took 2 to 3 minutes, so the whole routine was about 15 minutes a day. That made it realistic enough for a busy weeknight, which matters to me more than any cleaning idea that sounds good but takes 45 minutes to pull off.

3. The condition of the sills before day 1

Before starting, I looked closely at each sill and made notes. The kitchen window above the sink had water spots and a faint tacky line near the track. The dining room sill had a visible gray dust layer and 3 dead gnats in the corner. The mudroom sill was the dirtiest, with dried dirt specks and one small spider web tucked near the trim. The guest bedroom sill looked the cleanest but still had that dull film that shows up when sunlight hits at an angle.

I would call the overall dirt level moderate. Nothing was neglected beyond saving, but these weren’t freshly cleaned surfaces either. That helped me see whether the Listerine was truly doing anything or just making already-clean wood smell stronger.

4. How I applied the Listerine

Each day I started by dry-wiping away loose dust with a folded paper towel. I did this because any wet product, even one with alcohol, can turn dust into muddy streaks if you skip that first pass. After that, I used the damp microfiber cloth and wiped from left to right, paying extra attention to the back edge where the sill met the lower window frame.

For tight corners and track edges, I dipped cotton swabs into the Listerine and ran them along the seams. Then I followed immediately with a dry section of cloth so no liquid pooled in painted joints. If you try this at home, I really recommend that step. Window trim and older painted wood do not love sitting wet, even for a few minutes.

5. What happened on day 1

The first cleaning was the most dramatic because there was actual buildup to remove. The cloth came away gray-brown, especially from the kitchen and mudroom windows. The Listerine cut through the light sticky grime better than plain water would have, and the alcohol made the surface dry pretty quickly, usually within 2 to 4 minutes.

The biggest immediate difference was the shine. Not a glossy, polished shine, but more of a clean, brighter look. The painted sills looked less dull. The whole area also smelled very strongly medicinal for the first 20 minutes. That faded after about an hour, but on day 1 the scent was stronger than I would want if I were cleaning right before company came over for dinner.

6. What happened on days 2 and 3

By day 2, there was much less visible dirt coming up on the cloth. That told me the first day had done the heavy lifting. What I noticed instead was that the sills stayed looking neater between cleanings. The kitchen sill, which usually catches little black specks from the screen area, seemed easier to wipe down. Dust didn’t appear to cling quite as much, though I wouldn’t say it repelled dust completely.

On day 3, I began paying attention to bug activity. I did not see any dead insects appear because of the Listerine, and this was not some miracle insect-control situation. But I also didn’t find fresh spider web strands on the mudroom sill where I often see them. That could have been the repeated wiping as much as the product itself, so I want to be fair about that. Regular disturbance alone often keeps webs from settling in.

7. What happened on days 4 and 5

Days 4 and 5 were when the results leveled out. By then, I wasn’t removing grime so much as maintaining already-clean sills. The cloth showed only faint discoloration, mostly from normal household dust. The surfaces continued to look fresh, and sunlight made fewer streaks visible than I expected.

That said, one downside became more noticeable: the smell lingered in smaller rooms. In the guest bedroom, where the window stayed shut and the air didn’t circulate much, I could still catch a faint antiseptic scent 2 to 3 hours later. It wasn’t unbearable, but it also wasn’t cozy. As a mom, I’m always thinking about what makes a home feel comfortable, and this scent is not exactly “warm apple pie.” It’s more “the medicine cabinet got ambitious.”

8. What happened on days 6 and 7

By the last 2 days, I had a pretty clear picture. The window sills looked consistently clean, and the routine definitely prevented buildup. The mudroom sill especially stayed tidier than usual, likely because I was removing dirt before it had time to settle into the little paint texture near the trim.

However, I also noticed that daily use did not keep improving the result after the first few days. There was no magical cumulative effect by day 7. The sills on day 7 looked nice, yes, but not dramatically better than they did on day 3 or 4. In other words, the first and second uses mattered most; after that, the benefit was mostly maintenance.

9. The biggest benefits I noticed

The first major plus was how well it freshened dingy-looking painted sills. On my test surfaces, the Listerine removed surface grime, dried fairly quickly, and left the painted wood looking brighter. The second benefit was convenience. I already had a bottle in the house, and using 2 tablespoons a day meant I used about 14 tablespoons total over the week, just under 1 cup.

I also liked that it handled those little corner areas surprisingly well when used with a cotton swab. In the kitchen, the seam where the sill met the frame had collected a thin line of dark dust, and by the end of the week that was gone. For homes with light household grime and dust, this was a practical shortcut.

10. The downsides and limits

The smell was the biggest downside for me. Original brown Listerine has a very strong, old-school medicinal scent, and while it fades, it does not vanish instantly. If anyone in your family is sensitive to strong smells, this may be a dealbreaker. I would not use it in a nursery, a small closed bedroom, or right before bedtime.

The second issue is surface caution. I only used it on painted interior wood that was in decent condition. I would not use it on raw wood, unsealed surfaces, natural stone window ledges, or anything with a delicate finish without spot-testing first. Alcohol and essential oils can be a little unpredictable. On damaged paint, repeated wiping could potentially dull weak spots or highlight areas where the finish is already worn.

11. Did it actually help with bugs?

This is where I think people can overpromise. In my house, I noticed less web reappearance on the mudroom sill and fewer little bug remnants hanging around, but I cannot honestly say the Listerine itself solved a pest problem. What helped most may have been the daily wiping, the removal of dust and debris, and the disruption of corners where spiders like to settle.

If you’re hoping this will replace proper pest control, screens in good repair, or sealing cracks, I don’t think it will. If your goal is simply to keep window sills cleaner and a little less inviting to cobwebs over the course of a week, then yes, I do think it can help modestly.

12. How it compared to my usual cleaners

Compared with warm soapy water, the Listerine was faster-drying and better at cutting through light sticky film. Compared with a standard all-purpose spray, I’d say it performed similarly on everyday grime but had a much stronger scent. Compared with disinfecting wipes, it was less convenient because I had to pour it and manage cloths, but it was better for getting into detail areas with cotton swabs.

If I rank them just for window sills, my usual all-purpose cleaner still wins for overall balance. It smells better, is made for household surfaces, and does the job without much fuss. Listerine earned points for being surprisingly effective in a pinch and for brightening the appearance of the painted wood.

13. My best tips if you want to try it

First, dust the sill before using any liquid. Even 30 seconds with a dry cloth will make the final result much better. Second, use a small amount. A lightly damp cloth works better than a soaked one. I found that about 1 teaspoon per sill was plenty for average-size windows.

Third, open the window or at least the room door for airflow if possible. Fourth, follow with a dry cloth to prevent pooling around joints, caulk lines, and trim corners. And finally, test a hidden spot first, especially if your paint is older than 5 to 7 years, chipped, or already a little tacky.

14. A picky-family and busy-household reality check

In a real family home, the best cleaning trick is the one you’ll actually repeat. I can see myself doing this occasionally in high-grime spots like the mudroom or the kitchen window above the sink, especially after summer. But I would not add daily Listerine wiping to my permanent routine. Once-a-week maintenance with a regular cleaner is more realistic for my household.

I also think this kind of experiment is a good reminder that consistency often matters more than the “secret” product. If I had wiped those same 5 sills every day with a mild household cleaner for 7 days, I suspect I would have ended up with similarly tidy results. The Listerine made it interesting, but the repeated attention did a lot of the work too.

15. My final verdict after 7 days

After one full week, my window sills were cleaner, brighter, and easier to maintain than when I started. Original brown Listerine did a solid job on dust, light grime, and those slightly sticky spots that collect near windows. It also seemed to help keep the sill areas less hospitable to cobwebs, though I’d call that a minor bonus, not a guaranteed pest fix.

Would I do it again? Yes, but selectively. For a quick September refresh on painted interior window sills, it worked better than I expected. For everyday use all over the house, I’d stick with products meant for household surfaces. If you try it, think of it as a once-in-a-while cleaning hack, not a miracle cure. Sometimes the best result is simply a cleaner sill, a little afternoon sunlight, and the satisfying feeling that one more overlooked corner of the house is finally taken care of.