diff --git a/validate_yaml.py b/validate_yaml.py
index 68df0f9..818840d 100755
--- a/validate_yaml.py
+++ b/validate_yaml.py
@@ -2,6 +2,7 @@
 """Load YAML data to ensure validity."""
 
 import os
+import sys
 import typing
 from datetime import date, timedelta
 
@@ -18,6 +19,18 @@ import agenda.types
 config = __import__("config.default", fromlist=[""])
 data_dir = config.PERSONAL_DATA
 
+currencies = set(config.CURRENCIES + ["GBP"])
+
+
+def check_currency(item: agenda.types.StrDict) -> None:
+    """Throw error if currency is not in config."""
+    currency = item.get("currency")
+    if not currency or currency in currencies:
+        return None
+    pprint(item)
+    print(f"currency {currency!r} not in {currencies!r}")
+    sys.exit(-1)
+
 
 def check_trips() -> None:
     """Check trips."""
@@ -34,6 +47,10 @@ def check_flights(airlines: set[str]) -> None:
     bookings = agenda.travel.parse_yaml("flights", data_dir)
     for booking in bookings:
         assert all(flight["airline"] in airlines for flight in booking["flights"])
+
+    for booking in bookings:
+        check_currency(booking)
+
     print(len(bookings), "flights")
 
 
@@ -45,7 +62,18 @@ def check_trains() -> None:
 
 def check_conferences() -> None:
     """Check conferences."""
-    conferences = agenda.conference.get_list(os.path.join(data_dir, "conferences.yaml"))
+    filepath = os.path.join(data_dir, "conferences.yaml")
+    conferences = [
+        agenda.conference.Conference(**conf)
+        for conf in yaml.safe_load(open(filepath, "r"))
+    ]
+    for conf in conferences:
+        if not conf.currency or conf.currency in currencies:
+            continue
+        pprint(conf)
+        print(f"currency {conf.currency!r} not in {currencies!r}")
+        sys.exit(-1)
+
     print(len(conferences), "conferences")
 
 
@@ -82,6 +110,8 @@ def check_accommodation() -> None:
             pprint(stay)
             raise
 
+        check_currency(stay)
+
     print(len(accommodation_list), "stays")