Buckinghamshire Healthcare NHS Trust was caring for nine coronavirus patients in hospital as of Tuesday, figures show.
The trust runs Wycombe Hospital, Stoke Mandeville Hospital, Amersham Hospital, Buckingham Community Hospital and Thame Community Hospital.
NHS England data shows the number of people being treated in hospital for Covid-19 by 8am on July 20 was up from four on the same day the previous week.
There were no beds occupied by Covid-19 patients four weeks ago in Buckinghamshire Healthcare NHS Trust.
Across England there were 3,894 people in hospital with Covid as of July 20, with 544 of them in mechanical ventilation beds.
The number of Covid-19 patients hospitalised nationally almost trebled in the last four weeks, while the number on mechanical ventilators more than doubled, increasing by 140%.
The figures also show that 17 new Covid patients were admitted to hospital in Buckinghamshire Healthcare NHS Trust in the week to July 18. This was up from five in the previous seven days.