Services listed under O
- Oak Tree Kindergarten Ltd (Ashcroft Road)
- Oak Tree Kindergarten Ltd (Lansdowne Road)
- Oakhouse Foods
- Oakley Lodge Nursing Home
- Oakwood Primary School
- Oasis Drop In Centre
- Occupational Therapy Service - Children's Social Care
- The Offenders’ Families Helpline
- OK Rehab
- OK2B
- Olesen Tuition - The German Lessons Specialist
- Olive Tree Primary School
- One Foundation Organisation
- One Nation Archery Club
- One Stop Advice Centre
- One to One, Couples & Psychosexual Counselling
- Online Learning College
- OnLineTraining Limited (OLT)
- Opticall
- Ormiston Families - Breaking Barriers
- Orthodox Church of St Alban the Protomartyr of Britain
- Osinachi Favour Njoku (Favour Njoku)
- Our Lady Help of Christians Roman Catholic Church
- Outside-iN
- Oxford Aunts