| OPERAGLASS WORKS LTD | £163k | FY2024 | |
| OPERATION AGRI | £213k | FY2024 | |
| OPERATION CHRISTMAS BOX | £119k | FY2024 | |
| OPERATION COMMUNITY HAMPER | £109k | FY2025 | |
| OPERATION EMOTION | £117k | FY2025 | |
| OPERATION FISTULA (UK) | £362k | FY2023 | |
| OPERATION IMPREZZA | £64k | FY2025 | |
| OPERATION KINDLE LTD | £114k | FY2025 | |
| OPERATION MOBILISATION | £8.3m | FY2024 | reserves below policy |
| OPERATION NOAH | £208k | FY2025 | |
| OPERATION ORPHAN | £302k | FY2024 | |
| OPERATION SMILE UNITED KINGDOM | £7.5m | FY2025 | |
| OPERATIONAL RESEARCH SOCIETY LIMITED | £1.4m | FY2024 | |
| OPOKA CHARITABLE INCORPORATED ORGANISATION | £242k | FY2025 | reserves below policy going concern trustee payments |
| OPORA | £79k | FY2025 | |
| THE OPPENHEIM-JOHN DOWNES MEMORIAL TRUST | £39k | FY2025 | |
| THE OPPIDAN FOUNDATION | £74k | FY2024 | |
| THE OPPO FOUNDATION | £102k | FY2024 | |
| OPPORTUNITIES R UN LIMITED | £38k | FY2025 | reserves below policy |
| OPPORTUNITY GREEN | £2.8m | FY2025 | |
| THE OPPORTUNITY GROUP | £145k | FY2025 | |
| OPPORTUNITY INTERNATIONAL UNITED KINGDOM | £3.1m | FY2025 | |
| OPPORTUNITY PLAYGROUP EYE | £56k | FY2025 | |
| OPPORTUNITY THROUGH EDUCATION | £56k | FY2025 | |
| OPSA UK | £47k | FY2024 | |
| OPTIGENE FOUNDATION | £231k | FY2025 | trustee payments |
| OPTIONS 4 CHANGE | £140k | FY2025 | |
| OPTIONS FOR INTERNATIONAL HEALTH | £931k | FY2025 | reserves below policy going concern |
| OPTIONS FOR LIFE | £2.2m | FY2025 | |
| OPTIONS FOR SUPPORTED LIVING | £11.7m | FY2025 | |
| OPTIONS PREGNANCY RESOURCE CENTRE CIO | £54k | FY2025 | |
| OPTIONS WELLBEING TRUST | £417k | FY2025 | going concern |
| OPUS - AN ORGANISATION FOR PROMOTING UNDERSTANDING OF SOCIETY | £122k | FY2025 | reserves below policy |
| OPUS 48 | £49k | FY2025 | |
| OPUS DEI CHARITABLE TRUST | £282k | FY2024 | |
| ORA CHOIR | £282k | FY2025 | |
| ORA VESIMCHA | £76k | FY2025 | |
| ORACH CHAIM FOUNDATION | £37k | FY2025 | |
| Oracle Head and Neck Cancer UK Limited | £648k | FY2024 | |
| THE ORAL AND DENTAL RESEARCH TRUST | £58k | FY2025 | |
| ORAL HEALTH FOUNDATION | £985k | FY2025 | |
| ORANGE TREE THEATRE LTD | £4.6m | FY2025 | |
| ORANGUTAN APPEAL UK | £665k | FY2023 | |
| ORANGUTAN LAND TRUST | £66k | FY2025 | |
| ORANGUTAN VETERINARY AID (OVAID) | £75k | FY2025 | |
| THE ORATORY OF ST PHILIP NERI AT BIRMINGHAM | £705k | FY2024 | |
| THE ORATORY OF ST. PHILIP NERI AT CARDIFF | £219k | FY2025 | |
| THE ORATORY PRIMARY SCHOOL ASSOCIATION OF PARENTS AND FRIENDS | £48k | FY2025 | |
| THE ORATORY SCHOOL TRUST | £40k | FY2025 | |
| THE ORATORY SCHOOLS ASSOCIATION | £10.9m | FY2025 | |
| ORAYSA UK LTD | £114k | FY2025 | |
| ORBIS CHARITABLE TRUST | £5.1m | FY2024 | |
| ORBIT THEATRE LIMITED | £29k | FY2024 | reserves below policy going concern |
| ORCHARD | £179k | FY2025 | |
| THE ORCHARD | £106k | FY2025 | |
| ORCHARD BAPTIST CHURCH | £157k | FY2024 | |
| ORCHARD BAPTIST CHURCH, COLCHESTER | £68k | FY2024 | |
| THE ORCHARD CHARITABLE FOUNDATION | £36k | FY2025 | trustee payments |
| Orchard Counselling | £30k | FY2025 | |
| ORCHARD HILL COLLEGE | £22.0m | FY2025 | |
| ORCHARD HOUSE SCHOOL EDUCATIONAL TRUST | £29k | FY2025 | |
| ORCHARD JUNIOR SCHOOL PTFA | £27k | FY2025 | |
| ORCHARD PARK PRE-SCHOOL (YORK) | £104k | FY2025 | |
| THE ORCHARD PRE-SCHOOL AND PLAYGROUP | £389k | FY2025 | going concern |
| ORCHARD SATURDAY CLUB | £94k | FY2025 | |
| THE ORCHARD TRUST | £5.4m | FY2025 | reserves below policy |
| ORCHARD VALE TRUST LIMITED | £3.2m | FY2025 | |
| THE ORCHARD WOMEN | £331k | FY2025 | |
| ORCHARDS | £326k | FY2025 | |
| ORCHESTRA FOR THE EARTH | £32k | FY2024 | trustee payments |
| ORCHESTRA OF ST JOHN'S LIMITED | £337k | FY2025 | |
| ORCHESTRA OF THE AGE OF ENLIGHTENMENT | £4.0m | FY2025 | going concern |
| THE ORCHESTRA OF THE CITY | £28k | FY2025 | |
| THE ORCHESTRA OF THE SWAN | £672k | FY2025 | reserves below policy |
| ORCHESTRAS LIVE | £1.1m | FY2025 | reserves below policy |
| ORCHID CANCER APPEAL | £730k | FY2025 | reserves below policy going concern |
| THE ORCHID SOCIETY OF GREAT BRITAIN | £32k | FY2025 | |
| ORDER OF AUGUSTINIAN RECOLLECTS - ST. RITA'S CENTRE | £256k | FY2024 | |
| THE ORDER OF AUGUSTINIAN RECOLLECTS CHARITABLE TRUST | £155k | FY2024 | |
| THE ORDER OF FRIARS MINOR | £1.7m | FY2025 | not a going concern |
| THE ORDER OF FRIARS MINOR CONVENTUAL | £704k | FY2024 | |
| ORDER OF HERMIT FRIARS OF ST AUGUSTINE (AUGUSTINIAN ORDER) | £600k | FY2025 | |
| THE ORDER OF MISSION | £35k | FY2024 | |
| THE ORDER OF ST. AUGUSTINE OF THE MERCY OF JESUS | £12.7m | FY2024 | |
| THE ORDER OF THE BRITISH EMPIRE CHAPEL FUND | £122k | FY2025 | |
| ORDER OF THE COMPANY OF MARY OUR LADY CIO | £424k | FY2025 | |
| THE ORDER OF THE CROSS | £643k | FY2025 | |
| THE ORDER OF THE MOST HOLY SAVIOUR OF SAINT BRIDGET HOLYWELL | £179k | FY2024 | |
| THE ORDER OF THE MOST HOLY SAVIOUR OF ST BRIDGET | £112k | FY2024 | |
| THE ORDERS AND MEDALS RESEARCH SOCIETY | £68k | FY2025 | |
| THE ORDERS OF ST JOHN CARE TRUST | £233.6m | FY2025 | |
| ORDINARY 2 EXTRAORDINARY | £248k | FY2025 | |
| ORDINARY LIFE PROJECT ASSOCIATION | £2.1m | FY2025 | going concern |
| ORDINARY LIFESTYLES | £3.3m | FY2025 | |
| ORFORD MUSEUM CIO | £33k | FY2025 | |
| ORFUND (ORPHAN RESCUE FUND) | £30k | FY2026 | |
| THE ORGANIC FAMILY FOUNDATION | £41k | FY2024 | |
| ORGANICARTS | £73k | FY2024 | |
| ORGANISATION DESIGN INSTITUTE | £96k | FY2025 | |
| THE ORGANISATION FOR NEW MUSIC AND SOUND | £922k | FY2025 | |
| ORGANISATION FOR REHABILITATION OF HANDICAPPED SRI LANKA | £25k | FY2025 | |
| ORGANISATION OF CULTURE AND CHARACTER | £1.5m | FY2025 | |
| ORGANISTS CHARITABLE TRUST | £72k | FY2024 | |
| ORIEL DAVIES GALLERY | £1.2m | FY2025 | |
| ORIEL MYRDDIN | £128k | FY2025 | |
| ORIEL MYRDDIN | £200k | FY2025 | |
| ORIEL SCIENCE | £152k | FY2025 | |
| ORIENT FOUNDATION FOR ARTS & CULTURE | £240k | FY2025 | |
| ORIENTAL BIRD CLUB | £130k | FY2025 | |
| THE ORIENTAL CERAMIC SOCIETY | £121k | FY2025 | |
| The Origin Foundation | £38k | FY2024 | |
| ORINOCO - THE OXFORDSHIRE SCRAPSTORE | £162k | FY2025 | going concern |
| ORISON CHARITABLE TRUST | £2.8m | FY2025 | |
| ORLEANS PRIMARY PARENT AND TEACHER ASSOCIATION | £72k | FY2025 | |
| ORLEY FARM ASSOCIATION | £36k | FY2025 | |
| ORLEY FARM SCHOOL TRUST | £9.6m | FY2025 | |
| THE ORMEROD TRUST FUND | £39k | FY2025 | |
| THE ORMESBY ST MICHAEL TOWN LANDS | £57k | FY2024 | |
| ORMESBY TABLE TENNIS CLUB | £80k | FY2025 | |
| ORMESBY VILLAGE PRE-SCHOOL | £412k | FY2025 | |
| ORMISTON FAMILIES | £7.7m | FY2025 | |
| THE ORMISTON TRUST | £436.9m | FY2025 | |
| ORMIYAD | £33k | FY2024 | |
| ORMSKIRK & DISTRICT SCOUTS | £180k | FY2025 | |
| ORMSKIRK CHRISTIAN FELLOWSHIP | £54k | FY2025 | |
| Ormskirk School Foundation Trust | £38k | FY2025 | |
| ORMSKIRK STREET UNITED REFORMED CHURCH, ST HELENS | £120k | FY2024 | |
| ORNITHOLOGICAL SOCIETY OF THE MIDDLE EAST, THE CAUCASUS AND CENTRAL ASIA | £64k | FY2024 | |
| THE ORP FOUNDATION | £275k | FY2024 | |
| ORPEN MEMORIAL HALL | £59k | FY2025 | |
| ORPHAIDS UK | £43k | FY2025 | reserves below policy |
| ORPHAN CARE AFRICA | £75k | FY2025 | |
| ORPHAN HOPE (INDIA) | £59k | FY2025 | |
| ORPHAN WELFARE TRUST | £40k | FY2025 | reserves below policy |
| ORPHANS IN NEED | £23.5m | FY2025 | |
| ORPHANS IN THE WILD | £35k | FY2025 | |
| THE ORPHEUS CENTRE TRUST | £5.1m | FY2025 | |
| ORPHEUS SINFONIA FOUNDATION | £218k | FY2025 | |
| ORPINGTON AND BROMLEY GATEWAY CLUB | £136k | FY2025 | |
| ORPINGTON BAPTIST CHURCH | £806k | FY2024 | |
| ORPINGTON FOOTBALL CLUB | £212k | FY2025 | |
| ORPINGTON METHODIST CHURCH | £207k | FY2025 | |
| ORPINGTON VILLAGE HALL TRUST | £153k | FY2024 | |
| THE ORR MACKINTOSH FOUNDATION LIMITED | £9.5m | FY2025 | |
| ORSETT AND BULPHAN SCOUT GROUP | £26k | FY2024 | |
| ORSETT VILLAGE HALL | £49k | FY2024 | |
| ORT UK FOUNDATION | £848k | FY2023 | reserves below policy |
| ORTERSHAM LIMITED | £102k | FY2025 | |
| THE ORTHODOX CHURCH OF SAINT SILOUAN | £69k | FY2024 | |
| THE ORTHODOX CHURCH OF ST CUTHBERT AND ST BEDE, DURHAM | £75k | FY2026 | |
| ORTHODOX CHURCH OF THE NATIVITY OF THE MOTHER OF GOD BRISTOL | £42k | FY2025 | |
| THE ORTHODOX COMMUNITY OF THE ASCENSION AND ST CHAD, RUGBY | £25k | FY2025 | |
| THE ORTHODOX EUCHARISTIC COMMUNITY IN SOUTH LONDON | £103k | FY2024 | |
| ORTHODOX PARISH OF ST BEGA, ST MUNGO AND ST HERBERT, KESWICK, CUMBRIA | £42k | FY2025 | |
| ORTHODOX PARISH OF ST EPHRAIM THE SYRIAN CAMBRIDGE | £69k | FY2025 | |
| THE ORTHODOX PARISH OF ST MARTIN AND ST HELEN, COLCHESTER | £48k | FY2024 | |
| THE ORTHODOX PARISH OF ST NICHOLAS THE WONDERWORKER IN LONDON OF THE DIOCESE OF SOUROZH: OF THE RUSSIAN ORTHODOX CHURCH IN BRITAIN AND IRELAND | £62k | FY2025 | |
| The Orthodox Parish of St Nicholas, Oxford | £194k | FY2025 | |
| ORTHOGERIATRIC RESEARCH FUND | £394k | FY2025 | |
| THE ORTHOPAEDIC INSTITUTE LIMITED | £319k | FY2024 | |
| ORTHOPAEDIC RESEARCH UK | £1.4m | FY2025 | |
| THE ORTHOPAEDICS CHARITABLE TRUST FUND | £40k | FY2025 | |
| ORTON LONGUEVILLE PLAYGROUP | £350k | FY2025 | |
| ORU PAANAI | £184k | FY2022 | |
| THE ORWELL FOUNDATION | £194k | FY2025 | trustee payments |
| ORWELL MENCAP | £2.1m | FY2025 | |
| ORWELL PARK SCHOOL EDUCATIONAL TRUST LTD | £5.1m | FY2025 | not a going concern |
| THE ORWELL PARK SCHOOL FOUNDATION | £27k | FY2025 | |
| OSBORNE HOUSE COMMUNITY NURSERY LTD | £549k | FY2025 | |
| THE OSBORNE TRUST | £157k | FY2025 | |
| OSCAR UK INFORMATION SERVICE FOR WORLD MISSION | £52k | FY2025 | reserves below policy |
| OSCAR'S PAEDIATRIC BRAIN TUMOUR CHARITY | £382k | FY2025 | |
| OSCARS | £145k | FY2025 | reserves below policy going concern |
| OSEL ENTERPRISES LIMITED | £1.4m | FY2025 | |
| OSHWAL ASSOCIATION OF THE UK | £2.1m | FY2025 | |
| OSMANI TRUST | £1.9m | FY2025 | |
| OSMOTHERLEY PRE-SCHOOL | £86k | FY2025 | going concern |
| OSPREY | £28k | FY2025 | |
| OSPREY LEADERSHIP FOUNDATION | £27k | FY2025 | |
| OSSETT WAR MEMORIAL COMMUNITY CENTRE CIO | £86k | FY2025 | |
| THE OSTACCHINI FAMILY CHARITABLE TRUST | £168k | FY2023 | |
| OSTEOPATHIC TRUSTS | £95k | FY2024 | reserves below policy |
| OSTEOPOROSIS 2000 | £44k | FY2025 | reserves below policy |
| OSTEOPOROSIS DORSET | £309k | FY2025 | |
| OSTRO FAYRE SHARE FOUNDATION | £711k | FY2024 | |
| OSUN ARTS FOUNDATION | £30k | FY2025 | |
| OSWALDKIRK VILLAGE HALL CIO | £40k | FY2025 | |
| OSWESTRY BORDERLAND ROTARY CLUB CHARITY | £27k | FY2025 | |
| OSWESTRY CHRISTIAN CENTRE | £29k | FY2025 | |
| OSWESTRY OTTERS SWIMMING CLUB | £92k | FY2025 | |
| OSWESTRY SCHOOL | £9.8m | FY2025 | |
| OSWESTRY STATION BUILDING TRUST LIMITED | £337k | FY2025 | |
| OSWESTRY TEAM TENNIS (OTT) LAWN TENNIS CLUB | £40k | FY2025 | |
| THE OTAGO UNIVERSITY TRUST | £32k | FY2024 | |
| THE OTAKAR KRAUS MUSIC TRUST | £319k | FY2024 | |
| OTFORD EVANGELICAL FREE CHURCH | £72k | FY2025 | |
| Otford Village Memorial Hall | £63k | FY2026 | |
| THE OTHER ROOM | £134k | FY2024 | |
| OTHERS FIRST FOUNDATION | £134k | FY2025 | |
| THE OTHERWISE CLUB | £271k | FY2025 | reserves below policy |
| THE OTHONA COMMUNITY | £134k | FY2025 | |
| OTLEY 2030 | £116k | FY2025 | |
| OTLEY FOODBANK | £29k | FY2024 | |
| OTLEY SAILING CLUB | £86k | FY2024 | |
| OTRA COSA NETWORK | £79k | FY2024 | reserves below policy |
| THE OTTER TRUST | £114k | FY2024 | trustee payments |
| OTTER VALLEY ASSOCIATION | £52k | FY2025 | |
| OTTERBOURNE VILLAGE HALL | £102k | FY2025 | |
| OTTERSHAW PARENT TEACHERS ASSOCIATION | £30k | FY2025 | |
| OTTERSHAW VILLAGE HALL | £28k | FY2024 | |
| OTTERSPOOL ANIMAL HAVEN | £166k | FY2025 | trustee payments |
| OTTERY ST MARY UNITED REFORMED CHURCH CHARITY | £66k | FY2024 | |
| OUCH (UK) | £33k | FY2025 | |
| OUGHTIBRIDGE WAR MEMORIAL RECREATION GROUND | £70k | FY2024 | |
| OUGHTIBRIDGE WESLEYAN REFORM CHAPEL | £30k | FY2025 | |
| OUGHTRINGTON PRE-SCHOOL | £95k | FY2025 | going concern |
| OULTON BROAD WATER SPORTS CENTRE | £89k | FY2025 | |
| OUNDLE BAPTIST CHURCH | £103k | FY2023 | going concern |
| OUNDLE MENCAP HOLIDAYS LTD | £76k | FY2024 | |
| OUNDLE ROAD BAPTIST CHURCH, PETERBOROUGH | £118k | FY2025 | |
| THE OUNDLE SCHOOL FOUNDATION | £1.9m | FY2024 | |
| OUR AIM APPEALS | £102k | FY2024 | |
| OUR BARN COMMUNITY | £218k | FY2025 | |
| OUR BIG PICTURE LTD | £257k | FY2025 | |
| Our Bolton NHS Charity | £191k | FY2025 | |
| OUR BUS BARTONS LIMITED | £47k | FY2025 | |
| OUR CENTRE | £328k | FY2025 | |
| OUR CHARTIST HERITAGE | £34k | FY2023 | reserves below policy going concern |
| OUR DAILY BREAD MINISTRIES TRUST | £2.6m | FY2025 | |
| OUR DEMENTIA CHOIR | £204k | FY2025 | |
| Our Food Trust | £127k | FY2025 | |
| OUR FREE MINDS CIO | £47k | FY2025 | |
| OUR FUTURE | £618k | FY2025 | |
| OUR FUTURE HEALTH | £97.9m | FY2025 | |
| OUR GOD GIVEN MISSION | £82k | FY2025 | going concern |
| OUR HIDDEN TREASURE | £111k | FY2025 | |
| OUR HOUSE COMMUNITY | £256k | FY2025 | |
| OUR JESUS LIVES MINISTRIES | £123k | FY2025 | |
| OUR KIDS | £19.3m | FY2024 | |
| OUR KIDS FIRST | £386k | FY2024 | |
| OUR KIDS FOUNDATION | £35k | FY2025 | |
| OUR LADY OF FIDELITY GENERAL TRUST | £160k | FY2023 | |
| OUR LADY OF RANSOM PRE-SCHOOL | £220k | FY2025 | |
| OUR LADY OF SION SCHOOL, WORTHING | £4.0m | FY2025 | reserves below policy |
| OUR LADY OF THE WAYSIDE PRE-SCHOOL | £79k | FY2025 | going concern |
| OUR LADY'S ABINGDON TRUSTEES LIMITED | £6.2m | FY2023 | reserves below policy going concern |
| OUR LADY'S CATHOLIC HIGH SCHOOL FUND | £138k | FY2024 | |
| OUR LADY'S FIRST STEPS PRE-SCHOOL | £817k | FY2025 | |
| OUR MOON EDUCATION | £139k | FY2025 | |
| OUR MYNACHDY COMMUNITY | £65k | FY2025 | |