People have been using wet wipes, kitchen roll and even newspaper as an alternative.
Thames Water has warned it has seen an almost 20% increase in blockages as people use alternatives to toilet paper during lockdown.
One of the so-called ragbergs - a clump of wet wipes, nappies and sanitary products - weighing 40kg was dragged from a sewer in Maidenhead.
The company has seen an increase of about 10 sewer blockages per day compared to normal.
This follows shoppers bulk-buying toilet paper, leaving others turning to alternatives such as wet wipes, tissues, kitchen roll and newspapers, it said.
Such items combine with fats, oils and grease when flushed down the toilet - creating fatbergs or ragbergs.
Stephen Sanderson, area network manager for Thames Water, said: "Wipes and things like kitchen roll if used instead of toilet paper can't go down the loo.
"As nasty as it sounds, if people do use them as a last resort, they need to be put in a bin and disposed of safely."
Thames Water said before the lockdown it was seeing a reduction of about 10% in blockages.
However, it has since seen a jump of up to 8% compared with the average for the same month in 2017 to 2019.