Is this banknote still acceptable in Switzerland?

This note belongs to the 8th series of banknotes. They are no longer legal tender, so banks do not have to accept them.

The eighth banknote series was issued between 1995 and 1998.

These banknotes were recalled as of 30 April 2021 and are thus no longer legal tender. They can be exchanged for an unlimited period of time at the Swiss National Bank at full nominal value.

Source

The 8th series bills are no longer legal tender as other answers have said.

They are still accepted by federal public institutions for payment (SBB/CFF/FFS and post offices) until October 30, 2021.

Many if not all banks offer to exchange or deposit the bills for their clients.

The central bank, Swiss National Bank, will exchange recalled bills, without fee or deadline, at its offices and designated institutions for anyone (subject to money laundering checks). You can find a list of offices and agencies here (including other instructions).

If you are unable to travel to Switzerland or an SNB agency, you can also mail bills to the SNB office and they will deposit the amount in your bank account, which does not have to be a Swiss one (but your bank may levy incoming wire fees). Of course, you should probably send it registered and insure the amount (at your own cost) if your country’s postal service allows it.

Businesses in Switzerland are no longer obligated to accept them, and many have already decided to no longer process them, e.g. poster taken at KFC:

("The 8th-series bills are no longer valid from 30 April 2021. Only CFF (Swiss Federal Railways) and the Swiss Post accept them. The National Bank exchanges them for new bills of equal value.")

For smaller shops and restaurants for whom the cost of cash processing is comparatively insignificant, they may still accept it.

Advice from inside Switzerland for those who want to save a trip to a bank if you don't have "enough" to make it worthwhile to go get "rid" of.

I had around 300 worth of CHF in 10s and 20s and noticed that old notes are accepted by parking and ticket machines, so if you are a train commuter that's where I would offload them. Also, I paid with some of the old notes in local restaurants they didn't seem to care.

I did get the old notes rejected (that's how I was first made aware of the issue) at the local supermarkets (Migros or Aldi I think).

Ofc the most appropriate solution would be to just go to the bank.

Heres a list:

APPENZELL Appenzeller Kantonalbank Bankgasse 2 CH-9050 Appenzell +41 71 788 88 88

CHUR Graubündner Kantonalbank Postplatz CH-7001 Chur +41 81 256 91 11

FRIBOURG Banque Cantonale de Fribourg Bd de Pérolles 1 CH-1700 Fribourg +41 848 223 223

GENEVA Banque Cantonale de Genève Quai de l’Ile 17 CH-1211 Geneva +41 58 211 21 00

GLARUS Glarner Kantonalbank Hauptstrasse 21 CH-8750 Glarus +41 844 773 773

LIESTAL Basellandschaftliche Kantonalbank Rheinstrasse 7 CH-4410 Liestal +41 61 925 94 94

LUCERNE Luzerner Kantonalbank Pilatusstrasse 12 CH-6002 Lucerne +41 844 822 811

SARNEN Obwaldner Kantonalbank Rütistrasse 8 CH-6060 Sarnen +41 41 666 22 11

SCHAFFHAUSEN Schaffhauser Kantonalbank Vorstadt 53 CH-8200 Schaffhausen +41 52 635 22 22

SCHWYZ Schwyzer Kantonalbank Bahnhofstrasse 3 CH-6430 Schwyz +41 58 800 20 20

SION Banque Cantonale du Valais Rue des Cèdres 8 CH-1950 Sion +41 848 765 765

STANS Nidwaldner Kantonalbank Stansstaderstrasse 54 CH-6370 Stans +41 41 619 22 22

ZUG Zuger Kantonalbank Bahnhofstrasse 1 CH-6300 Zug +41 41 709 11 11

From outside of Switzerland you can mail them to

Swiss National Bank Cashier’s Office, West Bundesplatz 1 CH-3003 Berne

Don't forget to attach:

Address (full last name, first name, full address including country)
IBAN of the account in your name
SWIFT BIC, name, and full address of the bank where the account is held

That's an eighth series banknote, which was replaced by the ninth series only in September 2019, so yes, it's legal tender and would be widely accepted in Switzerland as of 30 April 2021, they're no longer legal tender!

https://en.wikipedia.org/wiki/Banknotes_of_the_Swiss_franc

I would suggest trying another bank or money changer in Poland, although you may have a hard time.

I sent it via mail to Switzerland and SNB said that they will check it and send the money to my account.

In 2015, I found an even older CHF 50 banknote in my grandparents' house. It belonged to a series older than the 8th from which the picture is from. That one was no more legal tender since decades, for sure. Some Swiss coins found in the same box were stamped with the year 1960.

I went to inquire about at a local Raiffeisen bank branch (small office in a village in Valais), and they exchanged it against a current one. You too may have a chance doing so.