Customers have expressed shock and disappointment after their latest Bermuda Telephone Company bill included a 12-month back charge for calls they were not billed for by mistake.

Some business owners were asked to pay more than $800 on top of their November bill to make up for the error that BTC described as a “usage billing error back charge”.

A spokesperson for the company confirmed there had been an “issue” with a third-party system that affected business customers, but maintained it had been fixed and the BTC was “committed to resolving case by case”.

It is unclear exactly how many customers have been affected by the error that meant their bill was worked out on the basis they had 100 inclusive calls rather than 50 calls.

Some of those business owners landed with the back charge said they had contacted the Regulatory Authority to complain.

Walter Simmons told The Royal Gazette that he would refuse to pay the back charge.

“I was mortified when I got my bill to see that I was being charged an extra $346.20. I feel it is just not right,” he said.

“It is not my fault this error has been made, so to suddenly get hit with this huge bill on top of my usual monthly bill is just not fair.”

A second businesswoman, who asked not to be named, added: “I have been charged an extra $600 for the period I was undercharged. I have contacted the Regulatory Authority.

“The bills I received over the last year have not reflected that I have not been correctly charged, so from a business perspective it is their mistake not mine, so they should suck it up.”

A third small business owner, who spoke on condition of anonymity, said: “I feel that BTC is picking a fight with the customer over a mistake that was not the customer’s fault.

“In my mind it’s bad business practice and disappointing; especially as having complained about this I am still waiting to hear back from them.”

A fourth businesswoman, who asked not to be named, added: “I was as shocked as everyone else to get this back charge; and to have that attached to your November bill made it seem that it had to be paid at the same time as you monthly bill.

“Our back charge was about $850; I would have thought the least they could do was spread those repayments over a period of time rather than make the customer feel they had to pay it at the end of November.

“The most annoying thing is the uncertainly; I tried to contact the firm in the middle of November but have not heard anything back. What happens if I don’t pay the back charge by the end of November? Will my phones be cut off? As a business we can not afford that.”

A BTC spokesperson said the company had worked “proactively” to provide clear information to affected customers.

“We can confirm there was an issue with a third party system that resulted in a limited number of our business customers receiving services for which they were not invoiced,” the spokesperson said.

“No residential customers were affected by this and the system issue has now been fully rectified.

“We worked proactively to provide clear information to our affected customers, we understand the concern and frustration some have and remain committed to resolving case by case.”