Is AECOM overvalued or undervalued?

As of 24 October 2025, AECOM's valuation grade has moved from very expensive to expensive, indicating a shift in perception regarding its valuation. The company appears to be overvalued based on its current metrics, with a P/E ratio of 20, a Price to Book Value of 6.45, and an EV to EBITDA of 13.73. In comparison to its peers, AECOM's P/E ratio is notably lower than EMCOR Group, Inc. at 29.12 and Comfort Systems USA, Inc. at 38.72, suggesting that while it is expensive, it may not be as overvalued as some of its competitors.
Despite the overvaluation, AECOM has shown strong performance with a year-to-date return of 24.40%, significantly outperforming the S&P 500's 15.47% during the same period. However, over the longer term, its 10-year return of 186.50% lags behind the S&P 500's 227.29%, indicating potential concerns about sustained growth. Overall, AECOM's current valuation metrics and peer comparisons suggest it is overvalued in the current market context.