diff --git a/scripts/build_healthcare_campaigns_cron.py b/scripts/build_healthcare_campaigns_cron.py
index 2a4bfa6..21051af 100644
--- a/scripts/build_healthcare_campaigns_cron.py
+++ b/scripts/build_healthcare_campaigns_cron.py
@@ -301,20 +301,23 @@ def add_subscriber(list_id: int, email: str, name: str, attribs: dict) -> bool:
         return False
 
 
-def ensure_campaign(seg_key: str, list_id: int) -> int:
-    # Reuse an existing warmup campaign for this segment only if it's still
-    # ACTIVE (draft / running / paused / scheduled). A finished/cancelled one
-    # can't accept new subscribers or restart, so we create a fresh dated one --
-    # that also picks up the latest email template (the canonical hc_*.html).
+def ensure_campaign(seg_key: str, list_id: int, send_list_name: str | None = None) -> int:
+    # One campaign per (segment, day): each day's campaign is bound to that day's
+    # dedicated SEND list, so it mails ONLY that day's newly-imported slice. We
+    # therefore reuse a campaign only when it's the SAME day's campaign (matched by
+    # the dated name) and still active; we never reuse a prior day's campaign,
+    # because that would re-target an old slice. A finished/cancelled same-day
+    # campaign can't restart, so a fresh one is created (also picking up the latest
+    # canonical hc_*.html template).
     from datetime import date
     seg = SEGMENTS[seg_key]
     ACTIVE = {"draft", "running", "paused", "scheduled"}
+    dated = f"{seg['campaign_name']} - {date.today():%b %d %Y}"
     res = lm("/campaigns?per_page=100")
     for c in res.get("data", {}).get("results", []):
-        if c["name"].startswith(seg["campaign_name"]) and c.get("status") in ACTIVE:
+        if c["name"] == dated and c.get("status") in ACTIVE:
             return c["id"]
     body = open(template_path(seg_key)).read()
-    dated = f"{seg['campaign_name']} - {date.today():%b %d %Y}"
     payload = {
         "name": dated, "subject": seg["subject"], "lists": [list_id],
         "from_email": FROM_EMAIL, "type": "regular", "content_type": "richtext",
@@ -552,13 +555,29 @@ def warm_segment(seg_key: str, rows: list[dict], slice_n: int,
         return 0
 
     list_id = get_or_create_list(seg["list_name"], ["healthcare", "warmup", seg_key])
+    # Per-day SEND list: the campaign targets ONLY today's newly-imported slice,
+    # never the whole accumulated segment list. Without this, each day's campaign
+    # re-mailed every prior subscriber (the cumulative list), so the cohort
+    # imported on day 1 received the identical email every subsequent day -- a
+    # 5-6x repeat that burned reputation and blocklisted ~12% of the list. The
+    # persistent `list_id` is still used for dedup/records; the dated send list is
+    # what the campaign actually sends to, so every provider gets exactly one send.
+    from datetime import date
+    send_list_name = f"{seg['list_name']} - SEND {date.today():%Y-%m-%d}"
+    send_list_id = get_or_create_list(send_list_name,
+                                      ["healthcare", "warmup", seg_key, "daily-send"])
     n_ok = 0
     for r in todo:
         email = r["email"].strip().lower()
-        if add_subscriber(list_id, email, r.get("name") or "", attribs_for(r)):
+        # Add to BOTH the persistent segment list (dedup/records) and today's
+        # send list (the campaign's only audience).
+        ok = add_subscriber(list_id, email, r.get("name") or "", attribs_for(r))
+        add_subscriber(send_list_id, email, r.get("name") or "", attribs_for(r))
+        if ok:
             imported.add(email); n_ok += 1
     save_imported(seg_key, imported)
-    cid = ensure_campaign(seg_key, list_id)
+    # Campaign targets the per-day send list, NOT the cumulative segment list.
+    cid = ensure_campaign(seg_key, send_list_id, send_list_name)
     if start_campaign:
         try:
             lm(f"/campaigns/{cid}/status", {"status": "running"}, "PUT")
@@ -566,7 +585,8 @@ def warm_segment(seg_key: str, rows: list[dict], slice_n: int,
             # Already running raises; that's fine.
             if "already" not in str(e).lower():
                 print(f"[hc-cron]   {seg_key}: start warning: {e}")
-    print(f"[hc-cron]   {seg_key}: imported {n_ok} into list {list_id}; campaign={cid}")
+    print(f"[hc-cron]   {seg_key}: imported {n_ok} into list {list_id} "
+          f"(send list {send_list_id}); campaign={cid}")
     return n_ok