Why don’t we use Equity Value multiples instead of Enterprise Value multiples?

The simple reason is that Enterprise Value takes into account the entire business which is what is being acquired. Another way of thinking about it is that Enterprise Value represents all aspects of the business that are “available” to all investors, including both equity and debt investors.

While Equity Value only shows the value of the business available to equity shareholders, after debt holders have been paid. So, if you’re looking to value something to purchase, you must value the whole thing.