I never had my hearing tested at Costco, so I can’t say. Costco’s vision doctor near me did a great job, however, compared to a private vision doc, every bit as good as far as I could tell. That was not a free test, however. Costco charges for vision tests but not for hearing tests. I too would imagine the sound test quality varies from one Costco audiologist and one Costco sound booth to another, just as it does outside Costco, as suggested above.
Costco will accept recent hearing aid test results from outside audiologists to prescribe Costco aids, and if there was any question, of course, about how good or recent that data was, they’d redo the other’s test for free just as they do otherwise.
I set off some negative comments in another thread when I suggested that free hearing tests weren’t worth the paper they were printed on, but I wasn’t thinking of Costco or of private audiologists when I said that. It seems there is some variation on this by locale as to whether private audiologists charge for hearing tests. Around me, most if not all private audiologists charge about $75-125 for a basic but thorough hearing test, which should run probably 15-30 minutes in a sound-resistant booth to administer. Costco is still free. What I was beefing about are the 5-minute “screenings” that some mall stores offer, not in a sound-resistant booth. These are not good. These are a come-on to either get you in the door to pay for a more thorough hearing test they will find you need, or the “consultant” may cut right to the chase and suggest hearing aids if they can get away with that in that state. You want a real hearing test in a sound-resistant booth administered by a certified audiologist who says you need aids before springing for them.