Ysgol San Sior
| LA_code | 662 |
| LA_name | Conwy |
| EstablishmentNumber | 3307 |
| EstablishmentName | Ysgol San Sior |
| TypeOfEstablishment | Welsh establishment |
| EstablishmentStatus | Open |
| PhaseOfEducation | Not applicable |
| StatutoryLowAge | |
| StatutoryHighAge | |
| Boarders | Not applicable |
| NurseryProvision | Not applicable |
| OfficialSixthForm | Not applicable |
| Gender | Not applicable |
| ReligiousCharacter | |
| ReligiousEthos | |
| Diocese | Not applicable |
| AdmissionsPolicy | |
| TrustSchoolFlag | Not applicable |
| Trusts | |
| SchoolSponsorFlag | Not applicable |
| SchoolSponsors | |
| FederationFlag | Not applicable |
| Federations | |
| UKPRN | |
| FurtherEducationType | Not applicable |
| Street | Church Walks |
| Locality | Llandudno |
| Address3 | |
| Town | Conwy |
| County | |
| Postcode | LL30 2HL |
| SchoolWebsite | |
| TelephoneNum | 01492878149 |
| HeadTitle | |
| HeadFirstName | |
| HeadLastName | |
| Linkedestablishments | |