diff --git a/02-peer-protocol.md b/02-peer-protocol.md
index f61bd3cca..2e75c3853 100644
--- a/02-peer-protocol.md
+++ b/02-peer-protocol.md
@@ -843,6 +843,9 @@ A sending node:
   - MUST offer `amount_msat` greater than 0.
   - MUST NOT offer `amount_msat` below the receiving node's `htlc_minimum_msat`
   - MUST set `cltv_expiry` less than 500000000.
+  - if `option_wumbo_htlcs` is not negotiated:
+    - for channels with `chain_hash` identifying the Bitcoin blockchain:
+      - MUST set the four most significant bytes of `amount_msat` to 0.
   - if result would be offering more than the remote's
   `max_accepted_htlcs` HTLCs, in the remote commitment transaction:
     - MUST NOT add an HTLC.
diff --git a/09-features.md b/09-features.md
index b508bac70..e3e26e3dd 100644
--- a/09-features.md
+++ b/09-features.md
@@ -41,6 +41,7 @@ The Context column decodes as follows:
 | 20/21 | `option_anchor_outputs`          | Anchor outputs                                            | IN       | `option_static_remotekey` | [BOLT #3](03-transactions.md)         |
 | 22/23 | `option_anchors_zero_fee_htlc_tx` | Anchor commitment type with zero fee HTLC transactions   | IN       |                   | [BOLT #3][bolt03-htlc-tx], [lightning-dev][ml-sighash-single-harmful]|
 | 26/27 | `option_shutdown_anysegwit`         | Future segwit versions allowed in `shutdown`              | IN       |                   | [BOLT #2][bolt02-shutdown]   |
+| 32/33 | `option_wumbo_htlcs`                | Bitcoin HTLCs not limited to 32 bits                      | IN       |                   | [BOLT #2][bolt02-adding-htlcs]   |
 
 ## Requirements
 
@@ -84,6 +85,7 @@ This work is licensed under a [Creative Commons Attribution 4.0 International Li
 [bolt02-open]: 02-peer-protocol.md#the-open_channel-message
 [bolt03-htlc-tx]: 03-transactions.md#htlc-timeout-and-htlc-success-transactions
 [bolt02-shutdown]: 02-peer-protocol.md#closing-initiation-shutdown
+[bolt02-adding-htlcs]: 02-peer-protocol.md#adding-an-htlc-update_add_htlc
 [bolt04]: 04-onion-routing.md
 [bolt07-sync]: 07-routing-gossip.md#initial-sync
 [bolt07-query]: 07-routing-gossip.md#query-messages