diff --git a/README.md b/README.md
index b8f0bad..c703552 100644
--- a/README.md
+++ b/README.md
@@ -62,6 +62,7 @@ ynab accounts transactions <id>
 ```bash
 ynab categories list
 ynab categories view <id>
+ynab categories update <id> [--name <name>] [--note <note>] [--category-group-id <id>] [--goal-target <amount>]
 ynab categories budget <id> --month <YYYY-MM> --amount <amount>
 ynab categories transactions <id>
 ```
diff --git a/src/commands/categories.ts b/src/commands/categories.ts
index f8ba596..feea070 100644
--- a/src/commands/categories.ts
+++ b/src/commands/categories.ts
@@ -36,6 +36,71 @@ export function createCategoriesCommand(): Command {
       })
     );
 
+  cmd
+    .command('update')
+    .description('Update category details')
+    .argument('<id>', 'Category ID')
+    .option('--name <name>', 'New category name')
+    .option('--note <note>', 'New category note')
+    .option('--category-group-id <id>', 'Move to a different category group')
+    .option('--goal-target <amount>', 'Goal target amount (only if goal already exists)', parseFloat)
+    .option('-b, --budget <id>', 'Budget ID')
+    .action(
+      withErrorHandling(
+        async (
+          id: string,
+          options: {
+            name?: string;
+            note?: string;
+            categoryGroupId?: string;
+            goalTarget?: number;
+            budget?: string;
+          } & CommandOptions
+        ) => {
+          // Validate at least one field is provided
+          if (options.name === undefined && options.note === undefined && options.categoryGroupId === undefined && options.goalTarget === undefined) {
+            throw new YnabCliError(
+              'At least one field to update must be provided (--name, --note, --category-group-id, or --goal-target)',
+              400
+            );
+          }
+
+          // Validate name if provided
+          if (options.name !== undefined && options.name.trim() === '') {
+            throw new YnabCliError('Category name cannot be empty or whitespace', 400);
+          }
+
+          // Validate goal-target if provided
+          if (options.goalTarget !== undefined && isNaN(options.goalTarget)) {
+            throw new YnabCliError('Goal target must be a valid number', 400);
+          }
+
+          const updateData: {
+            name?: string;
+            note?: string | null;
+            category_group_id?: string;
+            goal_target?: number | null;
+          } = {};
+
+          if (options.name !== undefined) {
+            updateData.name = options.name.trim();
+          }
+          if (options.note !== undefined) {
+            updateData.note = options.note.trim() || null;
+          }
+          if (options.categoryGroupId) {
+            updateData.category_group_id = options.categoryGroupId;
+          }
+          if (options.goalTarget !== undefined) {
+            updateData.goal_target = amountToMilliunits(options.goalTarget);
+          }
+
+          const category = await client.updateCategory(id, { category: updateData }, options.budget);
+          outputJson(category);
+        }
+      )
+    );
+
   cmd
     .command('budget')
     .description('Set category budgeted amount for a month (overrides existing amount)')
diff --git a/src/lib/api-client.ts b/src/lib/api-client.ts
index e95ff12..f6bf6f8 100644
--- a/src/lib/api-client.ts
+++ b/src/lib/api-client.ts
@@ -159,6 +159,15 @@ export class YnabClient {
     });
   }
 
+  async updateCategory(categoryId: string, data: ynab.PatchCategoryWrapper, budgetId?: string) {
+    return this.withErrorHandling(async () => {
+      const api = await this.getApi();
+      const id = await this.getBudgetId(budgetId);
+      const response = await api.categories.updateCategory(id, categoryId, data);
+      return response.data.category;
+    });
+  }
+
   async getPayees(budgetId?: string, lastKnowledgeOfServer?: number) {
     return this.withErrorHandling(async () => {
       const api = await this.getApi();