re-waterproofing jacket

I bought washing liquid for waterproof clothing at Waitrose - not sure whether it protects or enhances.

I've also used Nikwax successfully - the use-in-the-washing machine one.

Def Nikwax. I use their TX-Direct wash-in as mentioned by Firecracker 123.
I've used it in the machine for Paramo jacket and trousers and also for an inexpensive roll up showerproof jacket I got in The Original Factory Shop (TOFS).

I too like the Nikwax that you can wash in, and think ti is excellent on 'lightweight' fabric - you can't really use it on a thick interlined jacket.
I have a fabulous waterproof lightweight jacket that rolls down into a tiny space - 10 years old now, kept going with Nikwax (though I might realy only describe it as 'water-resistant' now)

Nikwax user here, too! I use the spray-on type. I've found that it's OK to use the one for tents etc on clothing, even though it's not recommended. The tent one is half the price!

I use the Nikwax that you use in the washing machine...a lot less messy and it works! You can get other brands online or from shops like Millets.

Message withdrawn at poster's request.

I use Nikwax for my Paramo walking gear it's excellent but only for certain fabric you would need to check.