In order to file your GST, regardless of the filing period, your monthly reconciliations need to be completed up to your period deadline. In order for your bookkeeper to complete your reconciliations, they will need:
Just starting your business? Do you need to register for GST? Visit https://www.canada.ca/en/revenue-agency/services/tax/businesses/topics/gst-hst-businesses/when-register-charge.html
If you need to register and you are not sure how to do so, visit https://www.canada.ca/en/revenue-agency/services/tax/businesses/topics/gst-hst-businesses/account-register.html to find out how.
Not sure whether you need to charge GST? Visit https://www.canada.ca/en/revenue-agency/services/tax/businesses/topics/gst-hst-businesses/charge-collect-which-rate.html for more information
Do you know your GST Filing and payment deadlines? Visit https://www.canada.ca/en/revenue-agency/services/tax/businesses/topics/gst-hst-businesses/complete-file-when.html or see below chart.