diff --git a/electrum/lnpeer.py b/electrum/lnpeer.py
index bd94eedfa..3f8c35242 100644
--- a/electrum/lnpeer.py
+++ b/electrum/lnpeer.py
@@ -2119,6 +2119,7 @@ class Peer(Logger):
         else:
             raise Exception(f"unexpected {mpp_resolution=}")
 
+        # TODO check against actual min_final_cltv_expiry_delta from invoice (and give 2-3 blocks of leeway?)
         if local_height + MIN_FINAL_CLTV_DELTA_ACCEPTED > htlc.cltv_abs:
             if not already_forwarded:
                 log_fail_reason(f"htlc.cltv_abs is unreasonably close")
diff --git a/electrum/lnworker.py b/electrum/lnworker.py
index f79560043..1d799de38 100644
--- a/electrum/lnworker.py
+++ b/electrum/lnworker.py
@@ -2146,9 +2146,10 @@ class LNWallet(LNWorker):
             payment_hash: bytes,
             amount_msat: Optional[int],
             message: str,
-            expiry: int,
+            expiry: int,  # expiration of invoice (in seconds, relative)
             fallback_address: Optional[str],
             channels: Optional[Sequence[Channel]] = None,
+            min_final_cltv_expiry_delta: Optional[int] = None,
     ) -> Tuple[LnAddr, str]:
         assert isinstance(payment_hash, bytes), f"expected bytes, but got {type(payment_hash)}"
 
@@ -2169,12 +2170,14 @@ class LNWallet(LNWorker):
         amount_btc = amount_msat/Decimal(COIN*1000) if amount_msat else None
         if expiry == 0:
             expiry = LN_EXPIRY_NEVER
+        if min_final_cltv_expiry_delta is None:
+            min_final_cltv_expiry_delta = MIN_FINAL_CLTV_DELTA_FOR_INVOICE
         lnaddr = LnAddr(
             paymenthash=payment_hash,
             amount=amount_btc,
             tags=[
                 ('d', message),
-                ('c', MIN_FINAL_CLTV_DELTA_FOR_INVOICE),
+                ('c', min_final_cltv_expiry_delta),
                 ('x', expiry),
                 ('9', invoice_features),
                 ('f', fallback_address),
diff --git a/electrum/submarine_swaps.py b/electrum/submarine_swaps.py
index 84ecd7cf8..6b5fb5480 100644
--- a/electrum/submarine_swaps.py
+++ b/electrum/submarine_swaps.py
@@ -50,9 +50,11 @@ LOCKUP_FEE_SIZE = 153 # assuming 1 output, 2 outputs
 MIN_LOCKTIME_DELTA = 60
 LOCKTIME_DELTA_REFUND = 70
 MAX_LOCKTIME_DELTA = 100
+MIN_FINAL_CLTV_DELTA_FOR_CLIENT = 3 * 144  # note: put in invoice, but is not enforced by receiver in lnpeer.py
 assert MIN_LOCKTIME_DELTA <= LOCKTIME_DELTA_REFUND <= MAX_LOCKTIME_DELTA
 assert MAX_LOCKTIME_DELTA < lnutil.MIN_FINAL_CLTV_DELTA_ACCEPTED
 assert MAX_LOCKTIME_DELTA < lnutil.MIN_FINAL_CLTV_DELTA_FOR_INVOICE
+assert MAX_LOCKTIME_DELTA < MIN_FINAL_CLTV_DELTA_FOR_CLIENT
 
 
 # The script of the reverse swaps has one extra check in it to verify
@@ -443,6 +445,7 @@ class SwapManager(Logger):
             our_privkey: bytes,
             prepay: bool,
             channels: Optional[Sequence['Channel']] = None,
+            min_final_cltv_expiry_delta: Optional[int] = None,
     ) -> Tuple[SwapData, str, str]:
         """creates a hold invoice"""
         if prepay:
@@ -458,6 +461,7 @@ class SwapManager(Logger):
             expiry=300,
             fallback_address=None,
             channels=channels,
+            min_final_cltv_expiry_delta=min_final_cltv_expiry_delta,
         )
         # add payment info to lnworker
         self.lnworker.add_payment_info_for_hold_invoice(payment_hash, invoice_amount_sat)
@@ -471,6 +475,7 @@ class SwapManager(Logger):
                 expiry=300,
                 fallback_address=None,
                 channels=channels,
+                min_final_cltv_expiry_delta=min_final_cltv_expiry_delta,
             )
             self.lnworker.bundle_payments([payment_hash, prepay_hash])
             self.prepayments[prepay_hash] = payment_hash
@@ -666,6 +671,13 @@ class SwapManager(Logger):
             our_privkey=refund_privkey,
             prepay=False,
             channels=channels,
+            # When the client is doing a normal swap, we create a ln-invoice with larger than usual final_cltv_delta.
+            # If the user goes offline after broadcasting the funding tx (but before it is mined and
+            # the server claims it), they need to come back online before the held ln-htlc expires (see #8940).
+            # If the held ln-htlc expires, and the funding tx got confirmed, the server will have claimed the onchain
+            # funds, and the ln-htlc will be timed out onchain (and channel force-closed). i.e. the user loses the swap
+            # amount. Increasing the final_cltv_delta the user puts in the invoice extends this critical window.
+            min_final_cltv_expiry_delta=MIN_FINAL_CLTV_DELTA_FOR_CLIENT,
         )
         return swap, invoice