A total of 14 teams contested the league, including 12 sides from the 2011–12 season and two promoted from the
2012 I-League 2nd Division.
ONGC as champions and
United Sikkim as runners-up secured direct promotion from the 2012 I-League 2nd Division. ONGC returned to the I-League after a one-year absence, while United Sikkim made their debut in the I-League.
Stadium Changes Air India and Mumbai FC Due to the ongoing redevelopment of the
Cooperage Ground in
Mumbai which is the regular home for
Mumbai F.C. and
Air India FC in the
I-League both clubs will play at the
Balewadi Sports Complex in
Pune,
Maharashtra until it is complete.
ONGC The newly promoted
ONGC F.C. also usually play at the
Cooperage Ground in
Mumbai but due to the redevelopment the team decided to play at the
Ambedkar Stadium in
Delhi which is where the main company,
ONGC, are based. However it will only be for five home matches.
Goan clubs The four
Goan clubs in the
I-League,
Churchill Brothers,
Dempo,
Salgaocar, and
Sporting Clube de Goa, usually play their I-League matches at the
Fatorda Stadium in
Margao. However, due to a major revamp at the stadium in preparation for the
2013 Lusophony Games which will be held in Goa, the Goan home games for the I-League will be played at the
Duler Stadium and then the
Tilak Maidan Stadium from the end of January.
Stadiums and Locations {{Location map+ |India |width=400 |float=right |caption=Locations of teams in the 2012–13 I-League |places= {{Location map~ |India3 |mark=TransparentPlaceholder.png |marksize=1 |lat=20.00 |long=86.00 |label='''''' {{Location map~ |India3 |mark=TransparentPlaceholder.png |marksize=1 |lat=9.00 |long=86.00 |label=''''''
Personnel and kits Note: Flags indicate national team as has been defined under
FIFA eligibility rules. Players may hold more than one non-FIFA nationality.
Managerial changes Foreign players Restricting the number of foreign players strictly to four per team, including a slot for a player from
AFC countries. A team could use three foreign players on the field each game including a least one player from the AFC country. ==League table==