Activists will seek signatures on Tuesday in cities including Warsaw, Gdańsk, Katowice and Wrocław.
In most areas the signature collections will begin before noon in city centres.
In order to be debated by parliament, the proposed bill needs to be backed by 100,000 signatures by the end of August.
Alfred Bujara, the head of a major commercial trade union, voiced hope that MPs will pass the legislation.
“We are organising a coordinated gathering of signatures across the whole of Poland for one day to remind the public about our project and reach out to as many people as possible. The more signatures we are able to gather, the greater the pressure will be on MPs,” Bujara said.
The proposed bill would prevent shops opening on Sundays, though it allows multiple exceptions including petrol stations, bakeries, newsagents, some small shops and all shops at railway stations and airports.
The unions behind the bill claim that the restrictions would increase overall shop turnover as people would stockpile more goods.
Bujara also argued that the bill would have a major impact on how Poles spend their weekends.
“Restricting trading on Sunday will mean that people will find new ways of spending their free time other than going shopping. Restaurants and recreational services will gain from this,” he said.