Supplementary Planning Documents (SPDs) provide further details, guidance and principles on Local Plan policies.  

Following adoption of the Winchester District Local Plan 2040 in March 2026, some SPDs remain lawful material considerations but only where they are referenced in policies carried forward in the Local Plan. The weight attributed will be assessed on a case‑by‑case basis, and older SPDs may carry limited weight where they are out of step with current national planning policy 

New Local Plan Regulations introduced on 25 March 2026 changed the legal basis for SPDs. Only SPDs that complete all statutory stages and are adopted by 30 June 2026 can be adopted. After this date, there is no route for local planning authorities to adopt new SPDs.