diff --git a/runtime/lua/vim/_meta/api_keysets.lua b/runtime/lua/vim/_meta/api_keysets.lua
index a3c6b52409..a09b0dbf65 100644
--- a/runtime/lua/vim/_meta/api_keysets.lua
+++ b/runtime/lua/vim/_meta/api_keysets.lua
@@ -423,6 +423,7 @@ error('Cannot require a meta file')
 --- @field undo_restore? boolean
 --- @field url? string
 --- @field scoped? boolean
+--- @field _subpriority? integer
 
 --- @class vim.api.keyset.user_command
 --- @field addr? any
diff --git a/runtime/lua/vim/treesitter/highlighter.lua b/runtime/lua/vim/treesitter/highlighter.lua
index 9165550132..c0398bbe18 100644
--- a/runtime/lua/vim/treesitter/highlighter.lua
+++ b/runtime/lua/vim/treesitter/highlighter.lua
@@ -360,7 +360,10 @@ local function on_range_impl(
   local MAX_ROW = 2147483647 -- sentinel for skipping to the end of file
   local skip_until_row = MAX_ROW
   local skip_until_col = 0
+
+  local subtree_counter = 0
   self:for_each_highlight_state(win, function(state)
+    subtree_counter = subtree_counter + 1
     local root_node = state.tstree:root()
     ---@type { [1]: integer, [2]: integer, [3]: integer, [4]: integer }
     local root_range = { root_node:range() }
@@ -449,6 +452,7 @@ local function on_range_impl(
               conceal = conceal,
               spell = spell,
               url = url,
+              _subpriority = subtree_counter,
             })
           end
 
diff --git a/src/nvim/api/extmark.c b/src/nvim/api/extmark.c
index 9d6ed35e12..a14cf426f4 100644
--- a/src/nvim/api/extmark.c
+++ b/src/nvim/api/extmark.c
@@ -836,6 +836,15 @@ Integer nvim_buf_set_extmark(Buffer buffer, Integer ns_id, Integer line, Integer
       col2 = c;
     }
 
+    DecorPriority subpriority = 0;
+    if (HAS_KEY(opts, set_extmark, _subpriority)) {
+      VALIDATE_RANGE((opts->_subpriority >= 0 && opts->_subpriority <= UINT16_MAX),
+                     "_subpriority", {
+        goto error;
+      });
+      subpriority = (DecorPriority)opts->_subpriority;
+    }
+
     if (kv_size(virt_text.data.virt_text)) {
       decor_range_add_virt(&decor_state, r, c, line2, col2, decor_put_vt(virt_text, NULL), true);
     }
@@ -845,7 +854,8 @@ Integer nvim_buf_set_extmark(Buffer buffer, Integer ns_id, Integer line, Integer
     if (has_hl) {
       DecorSignHighlight sh = decor_sh_from_inline(hl);
       sh.url = url;
-      decor_range_add_sh(&decor_state, r, c, line2, col2, &sh, true, (uint32_t)ns_id, id);
+      decor_range_add_sh(&decor_state, r, c, line2, col2, &sh, true, (uint32_t)ns_id, id,
+                         subpriority);
     }
   } else {
     if (opts->ephemeral) {
diff --git a/src/nvim/api/keysets_defs.h b/src/nvim/api/keysets_defs.h
index e9a7637427..cb68d09186 100644
--- a/src/nvim/api/keysets_defs.h
+++ b/src/nvim/api/keysets_defs.h
@@ -62,6 +62,8 @@ typedef struct {
   Boolean undo_restore;
   String url;
   Boolean scoped;
+
+  Integer _subpriority;
 } Dict(set_extmark);
 
 typedef struct {
diff --git a/src/nvim/decoration.c b/src/nvim/decoration.c
index 7776adf185..2c64935b64 100644
--- a/src/nvim/decoration.c
+++ b/src/nvim/decoration.c
@@ -553,12 +553,12 @@ static void decor_range_add_from_inline(DecorState *state, int start_row, int st
     uint32_t idx = decor.data.ext.sh_idx;
     while (idx != DECOR_ID_INVALID) {
       DecorSignHighlight *sh = &kv_A(decor_items, idx);
-      decor_range_add_sh(state, start_row, start_col, end_row, end_col, sh, owned, ns, mark_id);
+      decor_range_add_sh(state, start_row, start_col, end_row, end_col, sh, owned, ns, mark_id, 0);
       idx = sh->next;
     }
   } else {
     DecorSignHighlight sh = decor_sh_from_inline(decor.data.hl);
-    decor_range_add_sh(state, start_row, start_col, end_row, end_col, &sh, owned, ns, mark_id);
+    decor_range_add_sh(state, start_row, start_col, end_row, end_col, &sh, owned, ns, mark_id, 0);
   }
 }
 
@@ -619,14 +619,15 @@ void decor_range_add_virt(DecorState *state, int start_row, int start_col, int e
     .data.vt = vt,
     .attr_id = 0,
     .owned = owned,
-    .priority = vt->priority,
+    .priority_internal = ((DecorPriorityInternal)vt->priority << 16),
     .draw_col = -10,
   };
   decor_range_insert(state, &range);
 }
 
 void decor_range_add_sh(DecorState *state, int start_row, int start_col, int end_row, int end_col,
-                        DecorSignHighlight *sh, bool owned, uint32_t ns, uint32_t mark_id)
+                        DecorSignHighlight *sh, bool owned, uint32_t ns, uint32_t mark_id,
+                        DecorPriority subpriority)
 {
   if (sh->flags & kSHIsSign) {
     return;
@@ -638,7 +639,7 @@ void decor_range_add_sh(DecorState *state, int start_row, int start_col, int end
     .data.sh = *sh,
     .attr_id = 0,
     .owned = owned,
-    .priority = sh->priority,
+    .priority_internal = ((DecorPriorityInternal)sh->priority << 16) + subpriority,
     .draw_col = -10,
   };
 
@@ -731,7 +732,7 @@ next_mark:
       break;
     }
     int const ordering = r->ordering;
-    DecorPriority const priority = r->priority;
+    DecorPriorityInternal const priority = r->priority_internal;
 
     int begin = 0;
     int end = cur_end;
@@ -739,7 +740,8 @@ next_mark:
       int mid = begin + ((end - begin) >> 1);
       int mi = indices[mid];
       DecorRange *mr = &slots[mi].range;
-      if (mr->priority < priority || (mr->priority == priority && mr->ordering < ordering)) {
+      if (mr->priority_internal < priority
+          || (mr->priority_internal == priority && mr->ordering < ordering)) {
         begin = mid + 1;
       } else {
         end = mid;
diff --git a/src/nvim/decoration.h b/src/nvim/decoration.h
index a1b0df21c2..08586eb238 100644
--- a/src/nvim/decoration.h
+++ b/src/nvim/decoration.h
@@ -37,7 +37,7 @@ typedef struct {
   int end_row;
   int end_col;
   int ordering;  ///< range insertion order
-  DecorPriority priority;
+  DecorPriorityInternal priority_internal;
   bool owned;  ///< ephemeral decoration, free memory immediately
   DecorRangeKind kind;
   // next pointers MUST NOT be used, these are separate ranges
diff --git a/src/nvim/decoration_defs.h b/src/nvim/decoration_defs.h
index 33670d1e3c..c392880818 100644
--- a/src/nvim/decoration_defs.h
+++ b/src/nvim/decoration_defs.h
@@ -36,6 +36,7 @@ enum {
 typedef kvec_t(struct virt_line { VirtText line; int flags; }) VirtLines;
 
 typedef uint16_t DecorPriority;
+typedef uint32_t DecorPriorityInternal;
 #define DECOR_PRIORITY_BASE 0x1000
 
 /// Keep in sync with hl_mode_str[] in decoration.h
diff --git a/test/functional/treesitter/highlight_spec.lua b/test/functional/treesitter/highlight_spec.lua
index 2f13793686..40d528a379 100644
--- a/test/functional/treesitter/highlight_spec.lua
+++ b/test/functional/treesitter/highlight_spec.lua
@@ -548,7 +548,7 @@ describe('treesitter highlighting (C)', function()
           lua = [[
             ; query
             (string) @string
-            ((comment) @comment (#set! priority 90))
+            (comment) @comment
             (function_call (identifier) @function.call)
             [ "(" ")" ] @punctuation.bracket
           ]],