diff --git a/db/migrations/005_quotejudge_receipt_compat.sql b/db/migrations/005_quotejudge_receipt_compat.sql
new file mode 100644
index 0000000..05ebabf
--- /dev/null
+++ b/db/migrations/005_quotejudge_receipt_compat.sql
@@ -0,0 +1,34 @@
+-- Receipt compatibility for all historical QuoteJudge schemas. Additive only.
+CREATE TABLE IF NOT EXISTS quote_judge_receipts (
+    id BIGSERIAL PRIMARY KEY,
+    receipt_id TEXT,
+    tenant_key TEXT NOT NULL,
+    comparison_id TEXT,
+    skill_name TEXT,
+    tool_name TEXT,
+    status TEXT,
+    input_hash TEXT,
+    result_hash TEXT,
+    receipt_json JSONB,
+    payload JSONB,
+    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
+);
+
+ALTER TABLE quote_judge_receipts ADD COLUMN IF NOT EXISTS receipt_id TEXT;
+ALTER TABLE quote_judge_receipts ADD COLUMN IF NOT EXISTS skill_name TEXT;
+ALTER TABLE quote_judge_receipts ADD COLUMN IF NOT EXISTS tool_name TEXT;
+ALTER TABLE quote_judge_receipts ADD COLUMN IF NOT EXISTS status TEXT;
+ALTER TABLE quote_judge_receipts ADD COLUMN IF NOT EXISTS input_hash TEXT;
+ALTER TABLE quote_judge_receipts ADD COLUMN IF NOT EXISTS result_hash TEXT;
+ALTER TABLE quote_judge_receipts ADD COLUMN IF NOT EXISTS receipt_json JSONB;
+ALTER TABLE quote_judge_receipts ADD COLUMN IF NOT EXISTS payload JSONB;
+
+UPDATE quote_judge_receipts
+SET tool_name = COALESCE(tool_name, skill_name),
+    skill_name = COALESCE(skill_name, tool_name),
+    payload = COALESCE(payload, receipt_json),
+    receipt_json = COALESCE(receipt_json, payload)
+WHERE tool_name IS NULL OR skill_name IS NULL OR payload IS NULL OR receipt_json IS NULL;
+
+CREATE INDEX IF NOT EXISTS quote_judge_receipts_tenant_idx
+    ON quote_judge_receipts (tenant_key, created_at DESC);