diff --git a/domain/abri/abandonment.py b/domain/abri/abandonment.py
index e75ca224d..c112949f7 100644
--- a/domain/abri/abandonment.py
+++ b/domain/abri/abandonment.py
@@ -1,7 +1,7 @@
 from datetime import date
 from typing import Optional
 
-from domain.abri.models import AbandonReason
+from domain.abri.models import AbandonReason, UnsuccessfulOutcome
 
 
 def abandonment_date(
@@ -31,11 +31,13 @@ class UnmappableOutcomeError(Exception):
         super().__init__(f"no abandonment reason code for outcome {outcome!r}")
 
 
-# Only outcomes that trip the abandonment trigger (HubspotDealDiffer's
-# NEGATIVE_OUTCOMES) can reach here. Keyed on the outcome lower-cased, matching
-# how the differ compares. Tenant Refusal -> CRA is the client's steer but is
-# ambiguous (REFSURV/REFUSAL also fit) - confirmation pending, see the codes below.
-_REASON_BY_OUTCOME: dict[str, AbandonReason] = {
+# Only UNSUCCESSFUL_OUTCOMES can reach here (they trip the abandonment trigger),
+# keyed lower-cased to match how the differ compares. "cancelled"/"no show" are
+# deliberately unmapped for now - they never match the real "Cancelled / No Show"
+# dropdown value, so they cannot occur, and would raise loudly if they ever did.
+# Tenant Refusal -> CRA is the client's steer but is ambiguous (REFSURV/REFUSAL
+# also fit) - confirmation pending, see the reason-code reference below.
+_REASON_BY_OUTCOME: dict[UnsuccessfulOutcome, AbandonReason] = {
     "no answer": AbandonReason.CARDED,
     "tenant refusal": AbandonReason.CRA,
     "not viable": AbandonReason.NOACCESS,
@@ -49,10 +51,11 @@ def abandon_reason_for_outcome(outcome: Optional[str]) -> AbandonReason:
     case- and whitespace-insensitively. Raises UnmappableOutcomeError for an
     empty or unrecognised outcome, since abandon_reason is mandatory.
     """
-    reason = _REASON_BY_OUTCOME.get((outcome or "").strip().lower())
-    if reason is None:
-        raise UnmappableOutcomeError(outcome)
-    return reason
+    normalized = (outcome or "").strip().lower()
+    for mapped_outcome, reason in _REASON_BY_OUTCOME.items():
+        if mapped_outcome == normalized:
+            return reason
+    raise UnmappableOutcomeError(outcome)
 
 
 # Reason Code - Description
diff --git a/domain/abri/models.py b/domain/abri/models.py
index dc81e0ba7..0c32a78dc 100644
--- a/domain/abri/models.py
+++ b/domain/abri/models.py
@@ -7,6 +7,22 @@ PlaceRef = NewType("PlaceRef", str)
 
 SlotCode = Literal["AM", "PM", "AD"]
 
+# HubSpot deal outcomes (lower-cased) that mean a survey was unsuccessful and,
+# once the attempt threshold is reached, abandon the job. The single source of
+# truth shared by the abandonment trigger (etl HubspotDealDiffer) and the
+# reason-code mapping (domain.abri.abandonment).
+UnsuccessfulOutcome = Literal[
+    "no answer", "cancelled", "no show", "tenant refusal", "not viable"
+]
+
+UNSUCCESSFUL_OUTCOMES: tuple[UnsuccessfulOutcome, ...] = (
+    "no answer",
+    "cancelled",
+    "no show",
+    "tenant refusal",
+    "not viable",
+)
+
 
 class AbandonReason(str, Enum):
     """OpenHousing's coded reason a job was abandoned.
diff --git a/etl/hubspot/hubspot_deal_differ.py b/etl/hubspot/hubspot_deal_differ.py
index 22d7fb83c..9e2bd88fd 100644
--- a/etl/hubspot/hubspot_deal_differ.py
+++ b/etl/hubspot/hubspot_deal_differ.py
@@ -2,6 +2,7 @@ import os
 from typing import Any, Dict, List, Optional
 
 from backend.app.db.models.hubspot_deal_data import HubspotDealData
+from domain.abri.models import UNSUCCESSFUL_OUTCOMES
 from etl.hubspot.project_data import ProjectData
 from etl.hubspot.utils import parse_hs_bool, parse_hs_date, parse_hs_int
 
@@ -15,13 +16,7 @@ class HubspotDealDiffer:
     RETROFIT_DESIGN_COMPLETE = "uploaded"
     LODGEMENT_COMPLETE: List[str] = ["lodgement complete", "measures lodged"]
     ABANDONMENT_ATTEMPTS_THRESHOLD = 3
-    NEGATIVE_OUTCOMES: List[str] = [
-        "no answer",
-        "cancelled",
-        "no show",
-        "tenant refusal",
-        "not viable",
-    ]
+    NEGATIVE_OUTCOMES = UNSUCCESSFUL_OUTCOMES
     # Verified against the portal (2026-07-07): Abri stock-condition deals
     # carry no project association, so the project_code match is the branch
     # that fires in production; the id below is the project object id