CA certificate for refund on account of supply made to SEZ without payment of tax

You are correct! For unutilized Accumulated ITC refund, a CA certificate is not required. However, for a refund of accumulated ITC in case of supply to SEZ (Special Economic Zone) without payment, a CA certificate is required under Rule 89(2)(m) of the CGST Rules. Rule 89(2)(m) states that for a refund of accumulated ITC in case of supply to SEZ without payment, the applicant must submit a certificate from a chartered accountant or a cost accountant, certifying that the goods or services supplied to SEZ are in accordance with the provisions of section 16 of the IGST Act. So, to summarize: - No CA certificate required for unutilized Accumulated ITC refund. - CA certificate required for refund of accumulated ITC in case of supply to SEZ without payment, under Rule 89(2)(m).