no-unsafe-member-access

Disallow member access on a value with type any.

✅

Extending "plugin:@typescript-eslint/recommended-type-checked" in an ESLint configuration enables this rule.

💭

This rule requires type information to run.

The any type in TypeScript is a dangerous "escape hatch" from the type system. Using any disables many type checking rules and is generally best used only as a last resort or when prototyping code.

Despite your best intentions, the any type can sometimes leak into your codebase. Accessing a member of an any-typed value creates a potential type safety hole and source of bugs in your codebase.

This rule disallows member access on any variable that is typed as any.

Flat Config

eslint.config.mjs

export default tseslint.config({
  rules: {
    "@typescript-eslint/no-unsafe-member-access": "error"
  }
});

Legacy Config

.eslintrc.cjs

module.exports = {
  "rules": {
    "@typescript-eslint/no-unsafe-member-access": "error"
  }
};

Try this rule in the playground ↗

Examples

❌ Incorrect

declare const anyVar: any;
declare const nestedAny: { prop: any };

anyVar.a;
anyVar.a.b;
anyVar['a'];
anyVar['a']['b'];

nestedAny.prop.a;
nestedAny.prop['a'];

const key = 'a';
nestedAny.prop[key];

// Using an any to access a member is unsafe
const arr = [1, 2, 3];
arr[anyVar];
nestedAny[anyVar];

Open in Playground

✅ Correct

declare const properlyTyped: { prop: { a: string } };

properlyTyped.prop.a;
properlyTyped.prop['a'];

const key = 'a';
properlyTyped.prop[key];

const arr = [1, 2, 3];
arr[1];
let idx = 1;
arr[idx];
arr[idx++];

Open in Playground

Options

This rule is not configurable.

When Not To Use It

If your codebase has many existing anys or areas of unsafe code, it may be difficult to enable this rule. It may be easier to skip the no-unsafe-* rules pending increasing type safety in unsafe areas of your project. You might consider using ESLint disable comments for those specific situations instead of completely disabling this rule.

Related To

• Avoiding anys with Linting and TypeScript
• no-explicit-any
• no-unsafe-argument
• no-unsafe-assignment
• no-unsafe-call
• no-unsafe-return

---

Type checked lint rules are more powerful than traditional lint rules, but also require configuring type checked linting.

See Troubleshooting > Linting with Type Information > Performance if you experience performance degradations after enabling type checked rules.

Resources

• Rule source
• Test source