A record 689,313 alerts were sent to users of the NHS COVID-19 app in England and Wales in a week, NHS figures show.
The alerts tell people they have been in close contact with someone who has tested positive for coronavirus.
The new number was recorded in the week up to 21 July and is an 11.4% increase on the week before.
The previous week’s numbers showed 618,903 people were pinged by the app.
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Businesses in all sectors have complained that they are struggling to maintain operations when so many staff have been told to stay at home to break the transmission.
The government has said that some essential workers can now use daily testing to avoid having to isolate.
The car industry has joined calls for the government to bring forward the date for exempting fully-vaccinated adults from self-isolation rules.
It comes after a slump in production blamed on the so-called “pingdemic”.
Stock levels in relation to expected sales across the distribution sector reached a new record low this month, according to a key business survey.
Retailers are fretting over supplies and staffing as a result of the number of people being pinged.
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Raab ‘confident’ more countries set for green list
The number of alerts has been reported as the latest NHS Test and Trace figures show a total of 307,758 were confirmed to have coronavirus at least once in the week to 21 July.
597,260 people were identified as coming into close contact with someone who had tested positive.
This is the highest number recorded since 13 January.
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Meanwhile, the government has said it is “increasingly confident” more countries will soon be added to the amber and green travel lists.
Foreign Secretary Dominic Raab said he believes opportunities for international travel can in the near future be opened up further as “the momentum forward is positive”.
Mr Raab also did not rule out the possibility of popular holiday hotspot Spain moving to a different category in the government’s traffic light travel system at the next review point a week on Thursday.