2. Aries: Most & Least Compatible
Most
Fellow Fire signs Leo and Sagittarius are commonly named the most compatible, though Sagittarius takes the lead between the two. Sagittarius shares an adventurous and independent spirit with Aries, and they both would be able to give each other the freedom they need. 

Air signs Gemini and Aquarius are also excellent matches, as the Fire-Air combination is very complimentary and supportive. Aries also has the potential to work well with Libra, who is directly opposite the zodiac wheel.

Least
Cancer and Capricorn may be tough matches for Aries. Cancer is highly sensitive and may be too moody for Aries, and Aries may come across as too insensitive to Cancer. Capricorn is a very serious sign and may be too critical of Aries' impulsive and fiery nature.