Ratio analysis is one of the most widely used techniques for evaluating the financial condition of enterprises. However, whether the standard interpretation rules applied in ratio analysis adequately account for sectoral differences remains a debatable issue. This study comparatively examines the financial ratios of companies listed on Borsa Istanbul (BIST) on a sectoral basis. Using data from the Central Securities Depository Data Analysis Platform (VAP) for the 2016–2025 period, the industrial, wholesale and retail trade, and technology sectors are compared in terms of liquidity, financial structure, activity, profitability, and expense ratios. The study also employs DuPont decomposition, cash conversion cycle analysis, and a pre-post comparison of TAS 29 inflation accounting. Findings reveal that financial ratios differ systematically and significantly across sectors. While tangible fixed assets constitute 33.7% of total assets in the industrial sector, this ratio is merely 3% in the technology sector. DuPont decomposition demonstrates that sectors achieve return on equity through entirely different components. The negative cash conversion cycle (–19 days) in the trade sector provides concrete evidence that sectoral business models directly influence financial ratios. The implementation of TAS 29 reduced profitability ratios across all sectors, with the most pronounced effect observed in the tangible-asset-intensive industrial sector. The study concludes that ratio analysis cannot be interpreted independently of sectoral context and that meaningful ratio sets must be differentiated for each sector.