You can filter mail... I have been using ClearMyMail for several years. It collects the mail from your mailbox, runs it through it's spam profiles, then lets through those it considers are ok, or that you have told it to let contact you, and holds back all that which it considers is spam. It then emails you about those it is unsure about, giving you the opportunity to block it once, block it always, allow it once, or allow it always (add to whitelist).
I use it to check mail for my domain, then it sends the cleared messages on to my gmail account. You could try a free 30-day trial of it, see if you can set it up with your email system, see if it helps. Then decide to subscribe or not.. current yearly cost is £17.95.
Changing your email address is often the most effective thing, but there are other possibilities. Who is your email address with? They may have settings you can tweak to adjust your spam filtering.
I suspect that if it's with one of the major ISPs, you won't be able to do much directly and you may need a service that checks and cleans your email. I don't use anything like that, so I'm not in a position to advise. Mailwasher used to be recommended a lot. I don''t know if it's still around?
Ive always had the odd few spam emails every day, but in the last couple of months it's just got ridiculous. Forty or fifty messages every day; card services, PPI, gas courses, bingo. ...
I've read all the stuff online about how not to make it worse - I never reply to messages, or try to unsubscribe - but it persists and it's hard to see the one or two emails that I actually want to read. My IT consultant (my teenage son) says the only thing I can do is change my email address and only give out the new address to 'genuine' organisations, leaving the old address for the spammers. But I like my old address, and have had it for years - do any techy Mumsnetters have any advice?