Bristol City Council could become the first local authority in England to collect non-recyclable household rubbish only once every four weeks.
The council has launched a consultation on proposals aimed at boosting recycling rates from around 45% of its household waste to 65% by 2035.
A move to four-weekly collections would save the council £2.3m a year, while moving to three-weekly collections would save £1.3m a year.
The council forecasts these changes could stop between 7,000 and 10,000 tonnes of waste going to landfill or the incinerator.
A council spokesperson said a change in collection frequency would ‘increase the amount of waste our city recycles, reduce costs and significantly lower carbon emissions.’