diff --git a/grub-core/fs/btrfs.c b/grub-core/fs/btrfs.c
index 7bf8d922f..fa5d860eb 100644
--- a/grub-core/fs/btrfs.c
+++ b/grub-core/fs/btrfs.c
@@ -2337,11 +2337,16 @@ struct embed_region {
  * https://btrfs.wiki.kernel.org/index.php/Manpage/btrfs(5)#BOOTLOADER_SUPPORT
  * The first 1 MiB on each device is unused with the exception of primary
  * superblock that is on the offset 64 KiB and spans 4 KiB.
+ *
+ * Note: If this table is modified, also update
+ * util/grub-editenv.c::fs_envblk_spec, which describes the file-system
+ * specific layout of reserved raw blocks used as environment blocks so that
+ * both stay consistent.
  */
 
 static const struct {
   struct embed_region available;
-  struct embed_region used[6];
+  struct embed_region used[9];
 } btrfs_head = {
   .available = {0, GRUB_DISK_KiB_TO_SECTORS (1024)}, /* The first 1 MiB. */
   .used = {
@@ -2349,6 +2354,9 @@ static const struct {
     {GRUB_DISK_KiB_TO_SECTORS (64) - 1, 1},                        /* Overflow guard. */
     {GRUB_DISK_KiB_TO_SECTORS (64), GRUB_DISK_KiB_TO_SECTORS (4)}, /* 4 KiB superblock. */
     {GRUB_DISK_KiB_TO_SECTORS (68), 1},                            /* Overflow guard. */
+    {(GRUB_ENV_BTRFS_OFFSET >> GRUB_DISK_SECTOR_BITS) - 1, 1},     /* Overflow guard. */
+    {(GRUB_ENV_BTRFS_OFFSET >> GRUB_DISK_SECTOR_BITS), 1},         /* Environment Block. */
+    {(GRUB_ENV_BTRFS_OFFSET >> GRUB_DISK_SECTOR_BITS) + 1, 1},     /* Overflow guard. */
     {GRUB_DISK_KiB_TO_SECTORS (1024) - 1, 1},                      /* Overflow guard. */
     {0, 0}                                                         /* Array terminator. */
   }
diff --git a/include/grub/fs.h b/include/grub/fs.h
index df4c93b16..89e4d2b9b 100644
--- a/include/grub/fs.h
+++ b/include/grub/fs.h
@@ -132,4 +132,6 @@ grub_fs_unregister (grub_fs_t fs)
 
 grub_fs_t EXPORT_FUNC(grub_fs_probe) (grub_device_t device);
 
+#define GRUB_ENV_BTRFS_OFFSET (256 * 1024)
+
 #endif /* ! GRUB_FS_HEADER */
diff --git a/util/grub-editenv.c b/util/grub-editenv.c
index 1b923bf97..41bb86739 100644
--- a/util/grub-editenv.c
+++ b/util/grub-editenv.c
@@ -153,9 +153,16 @@ static fs_envblk_ops_t fs_envblk_ops = {
 
 /*
  * fs_envblk_spec describes the file-system specific layout of reserved raw
- * blocks used as environment blocks.
+ * blocks used as environment blocks. At present only Btrfs is supported. Other
+ * file-systems may be added if they provide a similar facility and avoid the
+ * limitation of writing to COW.
+ *
+ * Note: If this table is modified, also update
+ * grub-core/fs/btrfs.c::btrfs_head, which defines the layout in the Btrfs
+ * header and exports GRUB_ENV_BTRFS_OFFSET, so that both stay consistent.
  */
 static fs_envblk_spec_t fs_envblk_spec[] = {
+  { "btrfs", GRUB_ENV_BTRFS_OFFSET, GRUB_DISK_SECTOR_SIZE },
   { NULL, 0, 0 }
 };