Body Fat% is way off

I'm having the same issue. 

Tanita Ironman Scale Body Fat 10.5%

Withings Scale Body Fat 12%

Garmin S2 Scale, Body Fat 20% (Activity level 9), 24% (Activity level 6)

I’m having the same issue as you. Same reading same three scales. Funny cause I go to is always the Tania since it has the hand measurements as well. I am not 20% body fat. There has to be an error in the software. 

I only have one other scale to compare to, which is a Tanita body composition scale, and both scales are within .2 percent of each other for body fat. That's pretty close, almost exact. I am activity level 7. 

Same with mine when comparing the Index S2 to my old withings scale. within 2 or 3%

Oh, I didn't mean two percent, I meant it is only POINT 2% different (.2). So I am finding it completely accurate for me.  I wonder why some people get such different results.

Yep, .2% also. My withings is 10 years old. I'm going with Garmin being more accurate, but still very close to my vintage scale.

I LOVE this thing!  So accurate.  I get weighed at WW every week and this Garmin scale is exactly what the WW scale shows.  Their scales are from Tanita.

I am also around 10-12%. Seems like the scale expects 20-25% for everybody. 

Glad it's working for some people.  I might go the replace route and not simply return it.  However, can't say I have high hopes.