There are no grammar schools inside Ruislip, Eastcote or Harrow — the borough runs a fully comprehensive system. Families here who want a grammar-school route sit an 11+ for a neighbouring county or borough instead. Four systems are realistically in reach: Hertfordshire (Watford, partially selective, and the only one with HA5 written into its priority area), Buckinghamshire (Amersham/Chalfont, fully selective, reachable by the Metropolitan line), the Barnet superselectives (no catchment at all — distance only breaks ties), and the Slough Consortium (fully selective, one of which — Langley — names HA4 directly in its priority area). Each works differently, so "catchment" means something different at each one.
Why this matters for HA4 / HA5
Watford Grammar School for Boys and for Girls both name
HA5 1–5 directly in their published "Rest of the Admission Area" postcode list — one of the only grammar schools anywhere that explicitly includes an HA postcode. Everything else on this page has no fixed catchment reaching this far, so distance and travel time do the work instead.
South West Herts Consortium test (GL Assessment). Most places are non-selective community places; a minority are reserved for the top scorers. Watford is the closest realistic option to Ruislip/Eastcote/Harrow by distance. SW Herts runs 7 grammar schools in total under the same consortium test; the other three — Parmiter's, Rickmansworth School and Croxley Danes — sit further out or need a different route in, and are covered in our full guide alongside residency and relocation considerations. See our full guide to SW Herts grammar schools and relocating into the area.
Thinking about relocating?
Watford Grammar (Boys and Girls), Queens' and St Clement Danes are shown here because they're realistic without moving house — named HA5 priority postcodes, or a genuine test-route in. If you're weighing a move for one of the other three, our dedicated guide covers admission areas, oversubscription tie-breakers, and where HA4/HA5 families tend to relocate to:
SW Herts grammar schools — full guide →
Watford Grammar School for Boys
Rickmansworth Road, Watford, WD18 7JF
Partially selective
Boys, 11–18
Priority area confirmed
Admission basis146 community places (65%) allocated mostly by distance within the admission area; 78 specialist places (35%) split between academic-test and music aptitude, in a 60:40 split between the "Watford Area" and "Rest of Admission Area".
Priority postcodesWatford Area: WD17 1–4, WD18 0/6–9, WD19 4–7, WD23 1–7/9, WD24 4–7/9, WD25 0/5/7–9, WD3 3. Rest of Admission Area: WD3 1/4–9, WD4 8–9, WD5 0, WD6 3, WD7 7–8, HA3 6, HA5 1–5, HA6 1–3, HA7 3–4.
Realistic for this area?Yes for Pinner/Eastcote (HA5) — named in the priority postcodes. Less so for Ruislip (HA4) or Harrow-on-the-Hill (HA1–HA3), which fall outside the listed area entirely.
Watford Grammar School for Girls
Lady's Close, Watford, WD18 0AE
Partially selective
Girls, 11–18
Priority area confirmed
Admission basisSame structure as the Boys' school: a majority of non-selective community places prioritised by distance, plus a minority of academic (25%) and music (10%) places, split 60:40 between the two admission zones.
Priority postcodesIdentical admission area to the Boys' school, including HA5 1–5, HA3 6, HA6 1–3, HA7 3–4.
Realistic for this area?Yes for Pinner/Eastcote (HA5). The school's own published reach also mentions extending into the northern edges of Harrow and Hillingdon.
Queens' School
Aldenham Road, Bushey, Hertfordshire, WD23 2TY
Partially selective
Co-ed, 11–18
Priority area confirmed
Admission basis35% of places by academic test, 5% by music aptitude, 5% by sport aptitude — each open to any address. The remaining places go to Rule 5's named priority postcodes, which has been oversubscribed on its own for the past 5 years; only beyond that does distance apply to applicants outside the priority area.
Priority postcodesWD3–7, WD17–19, WD23–25, AL2 (south of M25), HA6, HA5 3**, HA5 4**, HA3 6**, HA7 3**, HA7 4**.
Realistic for this area?Yes for parts of Pinner/Eastcote — HA5 3 and HA5 4 specifically are named, though not the full HA5 1–5 range Watford covers. Not realistic for Ruislip (HA4) or most of Harrow-on-the-Hill.
St Clement Danes School
Chenies Road, Chorleywood, Rickmansworth, Hertfordshire, WD3 6EW
Partially selective
Co-ed, 11–18
No fixed catchment
Admission basisUses the same SW Hertfordshire Consortium test as Watford, but structured differently: ~10% of Year 7 places go by academic test score, a further ~10% by music aptitude test — both open to any address, address doesn't gate qualification. After siblings and staff children, the remaining ~80% of places go by straight-line distance, with no published priority postcode list.
Distance realityThe qualifying distance for the general (non-selective) intake has been shrinking in recent years, and Chorleywood, Rickmansworth and the immediate Hertfordshire villages sit considerably closer than Pinner or Eastcote.
Realistic for this area?Only via the academic or music test routes — those bypass distance entirely for initial qualification. The general distance-based majority of places is a real stretch from HA5, unlike Watford's named priority postcodes.
Buckinghamshire Secondary Transfer Test (STT), sat by all applicants regardless of catchment. All three schools below sit on the Metropolitan line's Amersham/Chesham branches, directly reachable from Ruislip, Eastcote and Northwood — the practical route in, even though none of their catchments reach this far. Buckinghamshire runs 13 grammar schools in total (all members of The Buckinghamshire Grammar Schools consortium); the other 10 — around Aylesbury, High Wycombe, Marlow, Beaconsfield, Burnham and Buckingham — sit on a different rail line or are considerably further, and are covered separately as relocation-tier options, not commutable ones. See our full guide to Buckinghamshire grammar schools and relocating into the county.
Thinking about relocating?
The three schools below are commutable without moving. If you're weighing a move into the county for one of the other ten, our dedicated guide covers residency rules, renting vs. buying, and where HA4/HA5 families tend to relocate to:
Buckinghamshire grammar schools — full guide →
Dr Challoner's Grammar School
Chesham Road, Amersham, Buckinghamshire, HP6 5HA
Fully selective
Boys, 11–18, co-ed sixth form
Admission basisPass the STT, then places are offered by oversubscription criteria that prioritise the school's defined catchment towns. Out-of-catchment applicants can still apply and are considered if places remain.
Catchment townsAmersham, Chesham, Chalfont St Giles, Chalfont Common, Gerrards Cross, Great Missenden, Prestwood — none of which include Ruislip, Eastcote or Harrow.
Realistic for this area?Reachable by Metropolitan line (Ruislip/Eastcote/Northwood to Amersham, roughly 25–35 min), but families here apply from outside the priority catchment, so the bar is effectively higher.
Dr Challoner's High School
Cokes Lane, Little Chalfont, Amersham, HP7 9QB
Fully selective
Girls, 11–18, co-ed sixth form
Admission basisSame Buckinghamshire STT and the same catchment-town model as Dr Challoner's Grammar School, its sister school.
Catchment townsAmersham, Chesham, Chalfont St Giles, Chalfont Common, Gerrards Cross, Great Missenden, Prestwood.
Realistic for this area?Same as its sister school — reachable via Chalfont & Latimer station on the Met line, applying from outside catchment.
Chesham Grammar School
White Hill, Chesham, Buckinghamshire, HP5 1BA
Fully selective
Co-ed, 11–18
Admission basisSame Buckinghamshire STT (qualifying score currently 121), then places go by oversubscription criteria prioritising the catchment area, before any remaining places go by distance — recent data shows distance offers reaching almost 9.7 miles in a typical year.
Catchment townsBroadly the whole Chiltern District — Amersham, Chesham, Chalfont St Giles, Chalfont St Peter, Great Missenden, Little Chalfont — plus a significant intake from Hertfordshire.
Realistic for this area?Chesham station is the terminus of the same Metropolitan line branch, directly reachable from Ruislip/Eastcote — and the school's own history notes pupils travelling in from North London via this route, even from outside catchment. Same pattern as the two Challoner's schools: reachable, but applying from outside the priority catchment.
A shared 11+ test (GL Assessment: English, Maths, Verbal & Non-Verbal Reasoning) sat once for all four schools; a score of 111+ makes a child eligible to be considered at any consortium school named on the application. Not on a direct train line from Ruislip, but close enough by road that private school coaches already run this route — several operators list Ruislip and Pinner as pick-up points. See our full guide to Slough Consortium grammar schools, including registration, key dates and how last year's allocation actually landed at each school.
Langley Grammar School
Reddington Drive, Langley, Slough, SL3 7QS
Fully selective
Co-ed, 11–18
Priority area confirmed
Admission basisPass the Slough Consortium 11+, then places go by a three-tier priority area, checked in order, before any remaining places go by distance.
Priority tiersArea 1 (Inner): SL3 7–0. Area 2 (Outer): SL0–4, TW18–20, UB3/4/7/8/10. Area 3 (General): SL5–9, TW3–15, UB1/2/5/6/9, HA1, HA2, HA3, HA4, HA5, HA6, W5/7/13, RG12/42.
Realistic for this area?The strongest match for Ruislip (HA4) of the four Slough schools — HA4 is named directly, albeit in the outer "General" tier, so it's a real but lower-priority route in.
Herschel Grammar School
Northampton Avenue, Slough, SL1 3BW
Fully selective
Co-ed, 11–18
Admission basisPass the Slough Consortium 11+, then priority goes to children living within 4 miles of the school in a straight line, measured to the front door, before any places go further afield.
Realistic for this area?Ruislip sits outside the 4-mile radius, so this is the least likely of the four Slough schools for an HA4 address, though still open to out-of-radius applicants if places remain.
Upton Court Grammar School
Lascelles Road, Upton, Slough, SL3 7PR
Fully selective
No catchment
Co-ed, 11–18
Admission basisNo area-based catchment. Priority instead goes to children currently attending Foxborough Primary School or Trevelyan Middle School; everyone else is considered on an equal footing after that.
Realistic for this area?Open to Ruislip families in principle, since there's no postcode barrier — the school's largest intake, so worth including on the CAF even without a local feeder-school link.
St Bernard's Catholic Grammar School
Langley Road, Slough, SL3 7AF
Fully selective
No catchment
Co-ed, 11–18, Catholic
Admission basisNo area-based catchment. After passing the 11+, priority runs through a faith-based order: children in care first, then practising baptised Catholics with a priest's reference, then other Christian denominations, before wider applicants.
Realistic for this area?Distance isn't the gating factor here — practising Catholic families have a real route in regardless of postcode; others are further down the priority order.
Barnet superselectives · no catchment
These schools don't use a catchment area at all. Anyone who meets the qualifying standard can apply; when a tie needs breaking, straight-line distance from home to school decides it. That makes them open to Ruislip/Eastcote/Harrow families in principle — the constraint is the daily journey, not the postcode.
Queen Elizabeth's School, Barnet (QE Boys)
Queen's Road, Barnet, EN5 4DQ
Fully selective
No catchment
Boys, 11–18
Admission basisGL Assessment test; places go by test score in rank order, regardless of address. If scores tie at the cut-off, straight-line distance to the school is the deciding factor.
Realistic for this area?Open to anyone who qualifies, but the journey from Ruislip/Harrow typically runs well over an hour each way by public transport — worth weighing before committing to daily travel at age 11.
The Henrietta Barnett School
Central Square, Hampstead Garden Suburb, London, NW11 7BN
Fully selective
No catchment
Girls, 11–18
Admission basisOwn two-round entrance exam (not GL Assessment). Round two invites the top 300 scorers from round one; final places go by combined score. Candidates within 3 miles of the school get priority for round two if marginal.
Realistic for this area?Similar travel profile to QE Boys — no catchment restriction, but a long cross-London journey from HA4/HA5.
St Michael's Catholic Grammar School
Nether Street, North Finchley, London, N12 7NJ
Fully selective
No catchment
Girls, 11–18, mixed sixth form
Admission basisSchool-set entrance test (English & Maths). Practising Catholic applicants with a Certificate of Catholic Practice are prioritised; distance is only used as a minor tiebreaker.
Realistic for this area?Relevant mainly for practising Catholic families — the faith criterion matters more here than proximity.