Using 309 interim reports of 103 FTSE350 LSE Companies in the period 2005 - 2007, the study investigated the relative information content of complementary and supplementary narrative commentaries in UK interim reports. Daily market adjusted cumulative abnormal returns ±5 days around the announcement of interim reports were applied using event studies. Narratives were captured by the disclosure variety and depth index - number of information items, good/bad news, amounts and comparison of current with past performance, reasons for performance and forward-looking. For disclosure variety, supplementary narratives had higher but insignificant importance than complementary narratives. For disclosure depth, complementary narratives had higher and significant importance than supplementary narratives. The results also show that complementary good news, complementary amounts and comparisons of current with past performance and complementary reasons for performance were associated with returns. The analysis should guide policymakers in stock markets, corporate executives, audit firms, regulators and investors, specifically after the financial crisis of 2008.