Organisations are asking customers to get in touch through digital platforms so that phone services can be freed up for urgent calls or vulnerable customers.
Trade group Contact Centre Network NI said the Covid-19 outbreak had meant more people than ever were making calls to services such as NHS 111 as well as banks, utilities and telecoms companies.
Where possible, contact centre workers were now working from home but some staff were still on premises.
However, full social-distancing guidelines and other measures had been put in place, with at least one bay between colleagues, as well as hand sanitiser installed on every bay and deep cleaning after every shift.
Jayne Davies, director of Contact Centre Network NI, said: "Over the last two weeks most call centres have seen an increase in call volumes as many people are at home and need assistance with vital issues by telephone. However, this high level of demand has a potential knock-on effect for vulnerable customers and those in most urgent need.
"The reality is that a significant number of those calling contact centres could be servicing their needs online. We would encourage them to do so to enable the most vulnerable to get through. And we would like to thank all the contact centre staff who continue to come in to work to support their customers and community during this very difficult time."