diff --git a/tests/test_plugin.py b/tests/test_plugin.py
index f0dc56c474b2..70639ff9632f 100644
--- a/tests/test_plugin.py
+++ b/tests/test_plugin.py
@@ -4360,6 +4360,11 @@ def test_sql(node_factory, bitcoind):
     # Make sure we have a node_announcement for l1
     wait_for(lambda: l2.rpc.listnodes(l1.info['id'])['nodes'] != [])
 
+    # Under valgrind, the senders can still be digesting the blocks
+    # above and pick a stale blockheight for the payments below, which
+    # the caught-up peers reject as expiry_too_soon.
+    sync_blockheight(bitcoind, [l1, l2, l3])
+
     # This should create a forward through l2
     l1.rpc.xpay(l3.rpc.invoice(amount_msat=12300, label='inv1', description='description')['bolt11'])