Utah officials say a possible dropped phone resulted in a typo that overvalued a home for almost $1 billion.

And taxpayers may have to pay for the mistake - with a tax hike over the next three years.

In May, an error was made which recorded a house built in 1978 as having a value of more than $987 million in the 2019 tax rolls.

In reality, the home should only have had a 2019 taxable value of $302,000.

Wasatch County Assessor Maureen 'Buff' Griffiths told officials last month a staff member may have dropped a phone on a keyboard. Griffiths said the 'horrific' and 'bizarre' mistake has resulted in a countywide overvaluation of more than $6 million.

'I'm thinking it was a data entry that would be something like they dropped their phone on the keyboard and it kicked out all these numbers without verifying. That's how crazy it was.'

An error was made which recorded a Utah home built in 1978 as having a value of more than $987 million in the 2019 tax rolls. Wasatch County Assessor Maureen 'Buff' Griffiths told officials last month a staff member may have dropped a phone on a keyboard

The blunder has since produced revenue shortfalls in five taxing entities, with budgets already approved. In Wasatch County’s budget, the shortfall is more than $1 million

Griffiths told The Deseret News that she estimates the error took place in May as her office was preparing tax rolls for a June deadline. However, the error wasn't caught until October - months after the tax rate was certified by the Utah State Tax Commission.

Clerk Cal Griffiths discovered the error when he studied a list of 'top 25' taxpayers, and reported the 'humongous number'.

Griffiths said the homeowner was 'none the wiser' about the error until they were contacted by the assessor's office.

But the blunder has since produced revenue shortfalls in five taxing entities, with budgets already approved.

In Wasatch County’s budget, the shortfall is more than $1 million. The Wasatch County Fire District will be short about $253,000, the Wasatch County Parks District will be short about $138,000, and Central Utah Water will be short about $217,000, according to a tax correction notice circulated by the county.

But the biggest blow is to Wasatch County School District, which is short about $4.4 million.

The school district's spokesman, John Moss, told The Deseret News that it would need to 'reduce spending and draw down from financial reserves'. That could impact ongoing teacher in-service programs and investment in professional development for staff.

'Teacher and staff salaries will not be impacted this year. However, some of the capital projects that were scheduled or proposed will need to be canceled or postponed due to lack of funds.'

Griffiths said the countywide windfall went unnoticed because it was 'chalked up to the booming county'

At an 'emergency meeting' on November 4, Griffiths said the countywide windfall went unnoticed because it was 'chalked up to the booming county'.

'Nobody was surprised the values were going up. Nobody. But we're going to check it moving forward, that yes, the values are going up but are they going up that much?'

County Manager Mike Davis said that there were checks in place that should have been looked at.

'We will modify those and in the future and do a better job.'