Can BT add up?

Matt168

Catching up on my admin at the end of May, I noticed that a recent BT bill did not add up. The two services came to a lower total than the amount charged, by the princely sum of 3p. I called BT and they said they would investigate, let me know what had happened and refund the difference. None of that has happened so far.

Has anyone else come across this? I can't believe it would be a unique situation - if they repeated this error over enough accounts it will add up to a reasonable amount. It would be nice to know that I can trust them to take the correct amount for my bill.

I'm curious if this breaches their DD guarantee too? They have taken the amount shown on the face of the bill, as per the screenshot below, but the bill itself was wrong. It doesn't even agree on their summary of the recent bills at the right of the total.

Neil_Jones

It'll almost certainly be a rounding error and the exact amounts of the service on a pedantic level will be something like £39.9949205, and the mobille is £15.5359391.

Much like energy providers don't just charge 7.5 per kWh of gas, it's usually something with about seven decimal places after it, but the amount is rounded up (or down) and presented to you as a 2 decimal place.

Over time accumulation of rounding errors will occasionally tip an extra penny or two appearing usually a few bills down the line.

Brie

Neil_Jones said:

It'll almost certainly be a rounding error and the exact amounts of the service on a pedantic level will be something like £39.9949205, and the mobille is £15.5359391.

Much like energy providers don't just charge 7.5 per kWh of gas, it's usually something with about seven decimal places after it, but the amount is rounded up (or down) and presented to you as a 2 decimal place.

Over time accumulation of rounding errors will occasionally tip an extra penny or two appearing usually a few bills down the line.

Perhaps but their IT boffins who design their bills should have added a bit to say that cell A (55.55) must equal cell B (55.52).  The number of times it is different will generate queries and complaints that will cost them far more than the 3p they might gain when A exceeds B.

Dazed_and_C0nfused

Neil_Jones said:

It'll almost certainly be a rounding error and the exact amounts of the service on a pedantic level will be something like £39.9949205, and the mobille is £15.5359391.

Much like energy providers don't just charge 7.5 per kWh of gas, it's usually something with about seven decimal places after it, but the amount is rounded up (or down) and presented to you as a 2 decimal place.

Over time accumulation of rounding errors will occasionally tip an extra penny or two appearing usually a few bills down the line.

Although quite how the sum of two rounded  elements could be 3 pence different is a bit odd?

Neil_Jones

Computer says no

Matt168

I would understand that if they rolled the roundings in to the totals for the relevant services. While I often see bills for other services that have unit prices that don't match the line charge, presumably due to those accumulations, I have never seen one that just doesn't add up. If it's an itemised bill, surely the bill value has to match the service subtotals?

Matt168

They still can't find an explanation on this. I can't imagine mine was the only bill where this happened but all BT customers are going to need to check the arithmetic on their bills and hope the error only produces small overpayments instead of substantial ones.

matelodave

Half a million customers at tuppence a go equals £10k, nice work if you can get away with it 

Jenni_D

matelodave said:

Half a million customers at tuppence a go equals £10k, nice work if you can get away with it 

But the fines they'd receive if this was investigated (by OFCOM?) and they were prosecuted would dwarf any additional revenue such a "scheme" would generate.  

Olinda99

If you want a broadband provider that can add up try Plusnet ..🙂

Matt168

Olinda99 said:

If you want a broadband provider that can add up try Plusnet ..🙂

I assumed that as they're part of BT they probably use the same billing platform. I might give Plusnet a go again when my contracts come round. We were with them a few years ago but could never get the router they supplied to work with something important (can't remember what now). It looks like they use the same kit as BT these days so it ought to be no worse than we're accustomed to...