Generally, it takes about 15 working days for bonus shares to be credited and reflected into your demat account and portfolio respectively, depending on the company. Once the bonus shares are credited to your Demat Account, the depository ( CDSL/NSDL) will notify you with the email intimation.

Initially, these shares are credited under a temporary ISIN and cannot be traded right away so the same will not be visible in your portfolio. Usually, it takes around 5 - 7 days for the scrip to transition from the temporary ISIN into the permanent ISIN. Once we receive confirmation from the exchange that the ISIN is now active then it will be visible in your portfolio. 

In case the shares are not credited within 15 working days or you haven’t received a confirmation email from depositories (CDSL/NSDL), please contact the company's RTA. You can find the registrar information on the NSE website under the 'Company Directory' tab and on the BSE website under the 'Corp Information' tab.