diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0faa84ac6..2f12999f1 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -14,8 +14,16 @@
 
 ## 89.0.0-SNAPSHOT - unreleased
 
+### 💥 Breaking Changes (upgrade difficulty: 🟢 LOW - grid column filter specs)
+
+* `GridFilterModelConfig.fieldSpecs` is no longer an allow-list. Any `filterable` column it omits
+  now gets a default filter - set `filterable: false` on columns that should have none.
+
 ### 🐞 Bug Fixes
 
+* Fixed `GridFilterModelConfig.fieldSpecs` disabling filters on all other `filterable` columns.
+  Apps can now pass a spec for just the fields needing custom config, such as a values renderer.
+  See Breaking Changes above.
 * Fixed the desktop `SegmentedControl` rendering 2px taller than adjacent buttons when `outlined`.
 
 ## 88.1.0 - 2026-10-01
diff --git a/cmp/grid/README.md b/cmp/grid/README.md
index 3c7e72ae0..9af477e5f 100644
--- a/cmp/grid/README.md
+++ b/cmp/grid/README.md
@@ -210,7 +210,8 @@ new GridModel({
     filterModel: true,  // Default config
     filterModel: {
         bind: store,    // Filter target (defaults to grid's store)
-        commitOnChange: true
+        commitOnChange: true,
+        fieldSpecs: [{field: 'status', renderer: statusRenderer}]  // Optional custom config
     },
     columns: [
         {field: 'status', filterable: true},  // Enable filter on specific columns
@@ -219,6 +220,10 @@ new GridModel({
 });
 ```
 
+A `filterable` column gets a filter with default config even if `fieldSpecs` omits its field, as
+long as that field exists in the bound Store or View.
+List only the fields that need custom config. Set `filterable: false` to disable a column's filter.
+
 ### Inline Editing
 
 ```typescript
diff --git a/cmp/grid/Types.ts b/cmp/grid/Types.ts
index 2c8d35b3d..4a0848772 100644
--- a/cmp/grid/Types.ts
+++ b/cmp/grid/Types.ts
@@ -163,6 +163,10 @@ export interface GridFilterModelConfig {
      * Specifies the fields this model supports for filtering. Should be configs for
      * {@link GridFilterFieldSpec}, string names to match with Fields in bound Store/View, or
      * omitted entirely to indicate that all fields should be filter-enabled.
+     *
+     * Any `filterable` column with a field not listed here gets a default spec, so this list only
+     * needs to include fields that require custom config. Set `filterable: false` on a column to
+     * disable its filter.
      */
     fieldSpecs?: Array<string | GridFilterFieldSpecConfig>;
 
diff --git a/cmp/grid/filter/GridFilterModel.ts b/cmp/grid/filter/GridFilterModel.ts
index 5c446e9ca..b69b25dac 100644
--- a/cmp/grid/filter/GridFilterModel.ts
+++ b/cmp/grid/filter/GridFilterModel.ts
@@ -77,6 +77,14 @@ export class GridFilterModel extends HoistModel {
         this.commitOnChange = commitOnChange;
         this.activeFilterIcon = activeFilterIcon ?? GridFilterModel.defaults.activeFilterIcon;
         this.fieldSpecs = this.parseFieldSpecs(fieldSpecs, fieldSpecDefaults);
+
+        // Ensure every filterable column has a spec, including columns or View fields added later.
+        // Columns are typically still empty here - the reaction covers the GridModel's setColumns().
+        this.addReaction({
+            track: () => [gridModel.columns, this.bind.fieldNames],
+            run: () => this.addColumnFieldSpecs(fieldSpecDefaults),
+            fireImmediately: true
+        });
     }
 
     /**
@@ -169,12 +177,29 @@ export class GridFilterModel extends HoistModel {
 
         return specs.map(spec => {
             if (isString(spec)) spec = {field: spec};
-            return new GridFilterFieldSpec({
-                filterModel: this,
-                source: bind,
-                ...fieldSpecDefaults,
-                ...spec
-            });
+            return this.createFieldSpec(spec, fieldSpecDefaults);
+        });
+    }
+
+    // Add default specs for filterable columns not covered by the configured specs.
+    private addColumnFieldSpecs(fieldSpecDefaults: Omit<GridFilterFieldSpecConfig, 'field'>) {
+        const {fieldNames} = this.bind;
+        this.gridModel.getLeafColumns().forEach(({filterable, field}) => {
+            if (filterable && fieldNames.includes(field) && !this.getFieldSpec(field)) {
+                this.fieldSpecs.push(this.createFieldSpec({field}, fieldSpecDefaults));
+            }
+        });
+    }
+
+    private createFieldSpec(
+        spec: GridFilterFieldSpecConfig,
+        fieldSpecDefaults: Omit<GridFilterFieldSpecConfig, 'field'>
+    ): GridFilterFieldSpec {
+        return new GridFilterFieldSpec({
+            filterModel: this,
+            source: this.bind,
+            ...fieldSpecDefaults,
+            ...spec
         });
     }