Chipotle Mexican Grill (CMG) had the highest return in July 2015 by a US stock in the S&P 500 (GSPC), returning 22.4%.

ASSET	MONTH	% RETURN
Chipotle Mexican Grill (CMG)	July 2015	22.42%
Amazon (AMZN)	July 2015	22.03%
Alphabet Inc Class A (GOOGL)	July 2015	20.94%
Netflix (NFLX)	July 2015	20.57%
Alphabet Inc Class C (GOOG)	July 2015	19.22%
Builders FirstSource (BLDR)	July 2015	15.34%
Monster Beverage (MNST)	July 2015	14.29%
Fortinet (FTNT)	July 2015	14.1%
Amgen (AMGN)	July 2015	13.97%
Take-Two Interactive Software (TTWO)	July 2015	13.92%
VeriSign (VRSN)	July 2015	13.7%
Walgreens Boots Alliance (WBA)	July 2015	13.58%
Royal Caribbean Cruises (RCL)	July 2015	12.37%
IDEXX Laboratories (IDXX)	July 2015	11.94%
Packaging Corp of America (PKG)	July 2015	11.85%
CH Robinson Worldwide (CHRW)	July 2015	11.72%
Hartford Financial Services (HIG)	July 2015	11.57%
Lockheed Martin (LMT)	July 2015	11.34%
Masco (MAS)	July 2015	11.27%
Expedia (EXPE)	July 2015	11.21%
Visa Inc Class A (V)	July 2015	10.89%
NVR (NVR)	July 2015	10.87%
F5 Networks (FFIV)	July 2015	10.79%
Altria (MO)	July 2015	10.78%
Bio-Techne (TECH)	July 2015	10.56%