One year. The validity period of electronic signature is one year. If the validity period is less than 90 days and greater than 15 days, the validity period will be extended by one year. If the validity period is less than 15 days or has expired, it will not be extended. If you want to continue to use it, please buy a new electronic signature. Electronic signature is a form of electronic signature. Using image processing technology, the electronic signature operation is transformed into the same visual effect as the paper document stamping operation.