| Abbreviation | Definition |
|---|---|
| ISC | ICAEW Student Council |
| ISCA | Institute of Singapore Chartered Accountants |
| ISN | Internal Sequence Number |
| ISO | Incentive Stock Option |
| ISRE | International Standard on Review Engagements |
| ITA | Israeli Tax Authority |
| ITAS | Implementation Tracking and Accounting System |
| ITBR | Invoices To Be Received |
| ITI | Irish Tax Institute |
| ITIN | Individual Taxpayer Identification Number |
| ITL | Interested Transaction List |
| ITR | Inquiry To Remittance |
| IVSC | International Valuation Standards Committee |
| IW | Installment Warrant |
| IW | Instalment Warrant |
| IWP | Institut Osterreichischer Wirtschaftsprufer (Austria) |
| IWTC | In-Work Tax Credit |
| JAAF | Journal of Accounting, Auditing and Finance |
| JAC | Joint Audit Committee |
| JACAL | Johnston Associates Chartered Accountants Limited |