There's no independent testing confirming that pet hair catcher balls reliably remove hair in the washing machine. The two most relevant mainstream sources — Bosch and Consumer Reports — address static and washer maintenance, not the performance of catcher balls as a product category.
What Bosch Actually Says
Bosch's guidance on dealing with pet hair in laundry mentions that dryer balls may help reduce static (source). That's about drying, not washing, and it's a hedged claim about static — not an endorsement of any washing-machine hair catcher ball or a claim about capturing fur during a wash cycle.
What Consumer Reports Actually Says
Consumer Reports' coverage of pet hair and washing machines focuses on how fur can clog pumps, filters, and drains over time, and recommends general washer maintenance habits to prevent damage (source). It does not evaluate hair catcher balls, lint traps, or similar accessories as products, and it makes no claim that any such device captures hair during the wash.

Why You Can't Generalize From These Sources
Neither source tests a specific catcher ball product, describes a universal mechanism for how such balls are supposed to work, or compares materials and designs across brands. That means claims like "removes 95% of pet hair" or "works in any washer" aren't supported by either source — they're marketing claims that need to be checked against the specific product's own documentation and, ideally, independent reviews.
In-Wash Capture vs. Post-Wash Collection
It's worth distinguishing two different things sold under similar names. Some products claim to grab hair during the wash cycle as water agitates the load. Others are designed to sit in the drain or filter area and collect hair after the cycle, as water drains out. These are different mechanisms with different failure modes, and a product's own manual or packaging — not a general appliance guide — is the only reliable way to know which one you're using and what it actually claims to do.
What To Do Before You Rely on One
Check your washing machine's own manual for guidance on pet hair and filter maintenance, since manufacturers vary in their recommendations and some filters need regular manual cleaning regardless of any catcher ball in use. Before washing, remove as much loose fur as possible — a portable pet hair remover glove during grooming and a reusable pet hair remover roller on blankets and clothing both reduce how much hair ever reaches the machine.

Bottom Line
Treat catcher ball claims skeptically until you've checked the specific product and your washer's manual. Reducing fur before it reaches the machine is the one step backed by common sense and consistent across every source.
Frequently Asked Questions
Do pet hair catcher balls actually work in the washing machine?
There's no independent test confirming generic catcher balls remove pet hair effectively. Bosch and Consumer Reports don't evaluate this product category, so performance depends on the specific product.
What does Consumer Reports say about pet hair and washing machines?
Its coverage focuses on how fur can clog washer pumps and filters over time and recommends general maintenance — it doesn't review or test hair catcher balls specifically.
What's the difference between in-wash and post-wash hair catchers?
In-wash designs claim to grab hair during agitation; post-wash designs sit in a drain or filter area and collect hair as water drains. Check the specific product to know which type you have.
How can I reduce pet hair reaching my washing machine?
Groom pets regularly with a hair remover glove and roll loose fur off blankets and clothing with a reusable roller before washing.