Every autumn my inbox fills with people asking which spray will make their bag "rainproof." The honest answer is that it depends entirely on what the bag is made of, and that for some materials the wrong spray does more harm than the rain would.
Let's sort it out by material, because that's the only thing that matters here.
Suede and nubuck: yes, spray it
Suede is the one material where a protector spray is close to essential. Untreated suede drinks up water and shows every drop as a dark spot. A dedicated suede protector — not a leather one — coats the tiny fibres and lets water bead and roll off. Do it before the first wear, hold the can far enough back that you get a fine mist rather than a wet patch, and reapply every few months. This genuinely transforms a rainy-day liability into a bag you can wear without anxiety.
Smooth leather: maybe, and carefully
Smooth leather is more water-resistant than people think — it's skin, and a light rain rolls off if the leather is conditioned. A wax-based waterproofing product can add real protection, but it will usually darken the leather, sometimes permanently, and it can dull a glossy finish. Test on the bottom corner first. If you love the current colour and shine, you may be happier just keeping it conditioned and carrying a small umbrella.
Canvas and coated fabric: light spray or nothing
- Plain canvas: a fabric protector spray helps a lot and won't hurt it.
- Coated canvas or PVC-coated fabric: already water-resistant by design. Save your money.
- Nylon: most of it sheds light rain fine on its own; the weak point is the zips and seams, not the fabric.
What sprays can't do
No spray makes a bag submersible. Water gets in through the top opening, the zip teeth, and the seams long before it soaks through treated leather or canvas. If you're caught in a real downpour, the spray is buying you minutes, not immunity. That's why the single best "waterproofing" move is behavioural: when the sky opens, tuck the bag under your coat or inside a large flat umbrella's shadow, and don't set it down in a puddle at the bus stop.
If it does get soaked
Don't panic and don't heat-dry it. Blot the outside with a towel, empty it, stuff it loosely with dry paper to pull moisture from the inside and hold the shape, and let it dry slowly at room temperature. For leather, once it's dry, condition it — a soaking pulls oils out and the leather will feel stiff until you put them back. For canvas, reshape while damp so it doesn't dry warped.
My actual routine
I keep a suede protector for my one suede crossbody and re-spray it seasonally. My leather totes get conditioner, not waterproofing, plus a compact umbrella that lives in the bag from October to March. That combination has kept everything looking good through several genuinely miserable winters, without a single darkened-leather regret. Match the product to the material and you'll spend less and protect more.