What should I do after submitting the Declaration Form? What supporting documents do I need to retain for SSG's future checks, if any?

If SSG needs any clarification regarding the information you have provided in your Declaration, SSG will contact you. Please retain all supporting documents.
Under the SDL Act and Regulations, every employer liable to pay SDL shall prepare and keep the following: Employee’s full name, gender, age, address, identity card number, nature of employment, rate and amount of wages, date of commencement and cessation of employment, and such other records for SSG to ascertain the levy payable by such employer.
SSG may also request for records such as the CPFB’s Record of Payment (Form 90 / 90A) and/or relevant payment screenshot as evidence of SDL payment.
This information is sourced from GB