The answer to this question appeared in studies at the beginning of the pandemic and ranged a few hours to 5 days, depending on the material.
But a group of researchers in Australia found viruses still "robust" after 28 days on smooth, non-porous surfaces, such as stainless steel bills, glass, vinyl and paper and polymer. The result was obtained by maintaining the environment at 20ºC, with a relative humidity of 50%. The researchers mention that these are examples of high-contact surface areas, such as glass on touch screens - such as cell phones - and stainless steel door handles.
On porous surfaces, such as cotton, the virus survived for approximately 14 days. On each surface, a drop of fluid containing the virus was used in concentrations similar to the levels observed in infected patients.
The research was conducted by the Commonwealth Scientific and Industrial Research Organization (CSIRO). The peer-reviewed study was published in the Virology Journal.