diff --git a/domain/abri/abandonment.py b/domain/abri/abandonment.py
index abf6e638e..e75ca224d 100644
--- a/domain/abri/abandonment.py
+++ b/domain/abri/abandonment.py
@@ -18,11 +18,80 @@ def abandonment_date(
     return confirmed_survey_date or last_submission_date
 
 
+class UnmappableOutcomeError(Exception):
+    """A deal outcome with no abandonment reason code to send to Abri.
+
+    abandon_reason is mandatory on a canceljob, so an empty outcome or one
+    outside the mapped set (which the abandonment trigger should never let
+    through) fails loudly rather than inventing a code.
+    """
+
+    def __init__(self, outcome: Optional[str]) -> None:
+        self.outcome = outcome
+        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] = {
+    "no answer": AbandonReason.CARDED,
+    "tenant refusal": AbandonReason.CRA,
+    "not viable": AbandonReason.NOACCESS,
+}
+
+
 def abandon_reason_for_outcome(outcome: Optional[str]) -> AbandonReason:
     """The OpenHousing abandonment reason code for a HubSpot deal outcome.
 
-    The single mapping point from HubSpot's outcome to a coded reason. For now
-    every outcome maps to CARDED; the real outcome-to-code table is a follow-up
-    (needs Abri's code list), and swapping it in is a one-place change here.
+    The single mapping point from HubSpot's outcome to a coded reason, matched
+    case- and whitespace-insensitively. Raises UnmappableOutcomeError for an
+    empty or unrecognised outcome, since abandon_reason is mandatory.
     """
-    return AbandonReason.CARDED
+    reason = _REASON_BY_OUTCOME.get((outcome or "").strip().lower())
+    if reason is None:
+        raise UnmappableOutcomeError(outcome)
+    return reason
+
+
+# Reason Code - Description
+# 1STCARD - 1st Card - Gas Service only
+# 2NDCARD - 2nd Card - Gas Service only
+# 2NDMAN - 2nd man required
+# ADDIT - Additional Work Required
+# APTB - Appointment Bought Forward [Note: I recognise this should read "brought" - they provided the list in a low res image and I'm pretty sure it says Bought not Brought]
+# ARCH - Job Archived
+# ASB - Anti Social Behaviour
+# ASSIGNED - Assigned to Different Operative
+# BULKABAN - Bulk Abandonment Request to IT
+# CARDED - Carded - Tenant not in
+# CONTRACT - Order raised using incorrect contract
+# CORON - Coronavirus
+# COVI - COVID-19
+# CPAL - CP Arrived Late
+# CRA - Customer Refused Access
+# DUPLICAT [not a typo] - Duplicate
+# ERROR - Issued in error
+# ESCA - Escalated to CAT1
+# HOLIDAY - Holiday
+# HS - Health & Safety
+# JOBD - Job Out of Date
+# M - Minor
+# MANAGE - Management decision
+# MATERIAL - Materials not available
+# MATREQ - Materials required
+# MYABRI92 - Tenant Cancelled On My Abri
+# NO ROOM - Room does not exist - invalid data
+# NOACCESS - No access
+# NOADULT - No Adult Present
+# OPTI - Cancelled in Optimise
+# OUTLOOK - Changed in Outlook
+# PASSED - Passed to other department
+# PLAN - Part of Planned Programme
+# RDCANX - Radian Direct Cancelled
+# RECALLMO - Recall Mobile Visit
+# REFSURV - Refused to Surveyor
+# REFUSAL - Agreed Resident Refusal
+# REQT - Requested by Tenant
+# RSCANX - Radian Services Canceled
diff --git a/domain/abri/models.py b/domain/abri/models.py
index a17cf82d5..dc81e0ba7 100644
--- a/domain/abri/models.py
+++ b/domain/abri/models.py
@@ -11,11 +11,14 @@ SlotCode = Literal["AM", "PM", "AD"]
 class AbandonReason(str, Enum):
     """OpenHousing's coded reason a job was abandoned.
 
-    Only CARDED is used for now; the full HubSpot-outcome-to-code table is a
-    documented follow-up - enum based on Abri codes needs creating and mapping from hubspot
+    Values are Abri's own reason codes. Only the members reachable from a
+    HubSpot abandonment outcome are defined; the outcome-to-code mapping lives
+    in domain.abri.abandonment.
     """
 
     CARDED = "CARDED"
+    CRA = "CRA"
+    NOACCESS = "NOACCESS"
 
 
 @dataclass(frozen=True)
diff --git a/tests/domain/abri/test_abandonment.py b/tests/domain/abri/test_abandonment.py
index 2fbeeb3e5..9ccd1cf03 100644
--- a/tests/domain/abri/test_abandonment.py
+++ b/tests/domain/abri/test_abandonment.py
@@ -3,7 +3,11 @@ from typing import Optional
 
 import pytest
 
-from domain.abri.abandonment import abandon_reason_for_outcome, abandonment_date
+from domain.abri.abandonment import (
+    UnmappableOutcomeError,
+    abandon_reason_for_outcome,
+    abandonment_date,
+)
 from domain.abri.models import AbandonReason
 
 CONFIRMED = date(2026, 6, 24)
@@ -23,14 +27,27 @@ def test_neither_date_leaves_the_abandonment_undated() -> None:
 
 
 @pytest.mark.parametrize(
-    "outcome",
-    ["no answer", "cancelled", "no show", "tenant refusal", "not viable", None],
+    ("outcome", "expected"),
+    [
+        ("No Answer", AbandonReason.CARDED),
+        ("NO ANSWER", AbandonReason.CARDED),
+        (" no answer ", AbandonReason.CARDED),
+        ("Tenant Refusal", AbandonReason.CRA),
+        (" tenant refusal ", AbandonReason.CRA),
+        ("Not Viable", AbandonReason.NOACCESS),
+        ("not viable", AbandonReason.NOACCESS),
+    ],
 )
-def test_every_outcome_currently_maps_to_the_carded_reason(
-    outcome: Optional[str],
+def test_a_triggering_outcome_maps_to_its_reason_code(
+    outcome: str, expected: AbandonReason
 ) -> None:
-    # Act
-    reason = abandon_reason_for_outcome(outcome)
+    assert abandon_reason_for_outcome(outcome) == expected
 
-    # Assert
-    assert reason == AbandonReason.CARDED
+
+@pytest.mark.parametrize(
+    "outcome",
+    [None, "", "   ", "surveyed", "epc completed", "not attempted", "cancelled / no show"],
+)
+def test_an_unmappable_outcome_raises(outcome: Optional[str]) -> None:
+    with pytest.raises(UnmappableOutcomeError):
+        abandon_reason_for_outcome(outcome)