Article 61 regulates the deduction of interest on loans, particularly in related-party scenarios. Interest is deductible for Omani companies (excluding banks/insurers) and for amounts allocated by an establishment or PE to its owner or head office, subject to control rules (Articles 132-133). The 'loan' definition covers various financial arrangements but excludes standard trade credit for goods/services where no interest is charged. Deductions must follow rules in the Executive Regulations. This provision targets 'thin capitalization' and ensures interest payments between related entities are commercially justified before reducing taxable income in Oman.