Yes , window cleaning in 2025 is still a profitable, steady side hustle. Dirty windows exist everywhere, and most people prefer hiring someone instead of doing it themselves. With startup costs under $150 and no special training required, anyone can begin.
You can work part-time and earn $300–$600 a month, or scale into a small business making $1,000+ monthly by adding commercial jobs. It’s not passive, but it’s flexible, low-cost, and highly future-proof, since windows will always need cleaning.