Typically, a grace period of 15 days is allowed for monthly mode of premium and 30 days for quarterly, half - yearly and yearly premium payment. (securenow.in)
Also, if the premium is paid at one go for the whole year the funds are available (for investment) to the company for longer than in monthly mode of payment. (tomorrowmakers.com)
For monthly modes of premium payment the grace period allowed is 15 days. (easypolicy.com)