Housing charity, Threshold, says the number of calls it receives trebled in the last three weeks of March.
It says the majority of people are now afraid of falling into rent arrears due to a loss of income because of the Covid-19 pandemic.
The charity is now worried about a potential spike in the number of homeless people after the government's measures to protect renters are lifted.
There is currently a ban on rent increases and evictions.
Threshold chief executive John-Mark McCafferty says the types of calls they are getting have changed;
"Most tenants impacted are seeking advice on rent supplements, followed by queries about tenancy terminations."
