This pairing can be a lot of fun. Both individuals are sensation seekers who crave new experiences and are not averse to a little (or a lot of) danger. These cheerful lovers of excitement and novelty can have many adventures together. Both tend to be optimistic and prone to risk taking, so neither will impose any restraint on the other (this pair can get themselves into all sorts of trouble, losing vast sums of money or even endangering their lives due to their mutual impulsivity, overconfidence, and lack of common sense). Money problems are particularly likely with this combination, as both signs tend to live extravagantly and well beyond their means, and neither is inclined to rein things in when prudence is warranted.
Aries and Sagittarius are usually quite compatible in day-to-day life. Both tend to be restless, active, exuberant, spontaneous, extroverted, and high-spirited, so they interact with the world in a similar manner and are unlikely to bore one another. Both also want some degree of independence within a relationship, and they can grant each other this much-needed personal freedom. In addition, they share a tendency toward optimism, which can help them get through rough times together.
On the negative side, neither sign is known for tact or diplomacy. Blunt, hurtful statements can lead to fights. However, both signs to tend to get over things quickly, and they share the positive quality of being able to laugh at themselves, which can help to smooth things over. Unless fights between these two are particularly nasty, a bit of conflict probably won’t tear their relationship apart.
Note: There is more to astrological compatibility than sun signs alone. Other elements in a person’s natal zodiac also play a role. Ascendants (rising signs), moon signs, and other planetary placements and aspects also shape personality and affect compatibility. For example, a Capricorn with Leo rising will be more extroverted than a typical Capricorn, and a Taurus with Aries rising or the moon in Sagittarius will be more compatible with Sagittarius than a typical Taurus. For more information on other natal chart elements, see Astrology Sun, Moon, and Ascendant.