Recently, while working on a TypeScript project, I got an error that says, “Property does not exist on type.” I tried different solutions to fix it. In this tutorial, I will explain how to fix the common TypeScript error “Property does not exist on type.”
Property Does Not Exist on Type Error in TypeScript
The “Property does not exist on type” error occurs when you try to access a property on an object that TypeScript does not recognize. This usually happens because TypeScript enforces strict type checking to prevent runtime errors.
For example, let’s say you have the following TypeScript code:
interface User {
name: string;
age: number;
}
const john: User = { name: "John Doe", age: 30 };
console.log(john.address);
In this example, TypeScript will throw an error because the address
property does not exist on the User
interface.
You can see the error like in the screenshot below:

Check out TypeScript TypeError: “is not a function”
Common Scenarios and Solutions
Now, let me show you a few scenarios when this error occurs and the solutions for it.
- Missing Property in Interface If you encounter this error, the first step is to check if the property is defined in the interface or type. If not, you need to add it.
interface User {
name: string;
age: number;
address?: string; // Optional property
}
const john: User = { name: "John Doe", age: 30 };
console.log(john.address); // No error
- Incorrect Type Declaration Sometimes, the error occurs because the type declaration is incorrect. Ensure that the type of the object matches the type definition.
interface Product {
id: number;
name: string;
price: number;
}
const product: Product = { id: 1, name: "Laptop", price: 999.99 };
console.log(product.price); // Correct type, no error
- Extending Types If you are working with objects that share common properties, consider using type extension to avoid repetitive code and errors.
interface Person {
name: string;
age: number;
}
interface Employee extends Person {
employeeId: number;
}
const employee: Employee = { name: "Alice", age: 28, employeeId: 1234 };
console.log(employee.employeeId); // No error
- Type Assertions In cases where you are sure about the type of an object but TypeScript is not, you can use type assertions to override TypeScript’s type checking.
const user = { name: "Bob", age: 25 } as User;
console.log(user.name); // No error
- Third-Party Libraries When using third-party libraries, you might encounter this error if the library’s type definitions are not up-to-date. You can either update the type definitions or use type assertions.
// Example with a hypothetical library
import { someLibraryFunction } from 'some-library';
const result = someLibraryFunction() as { data: string };
console.log(result.data); // No error
Debugging Tips
- Check Type Definitions: Always ensure your type definitions are correct and up-to-date.
- Use Optional Properties: If a property is not always present, make it optional in your type definition.
- Leverage TypeScript Tools: Use TypeScript’s built-in tools and IDE support to catch errors early.
Conclusion
In this tutorial, I explained the causes and solutions for the error “Property does not exist on type” in TypeScript. I hope this helps.
You may also like:
- How to Use TypeScript Optional Function Parameters?
- How to Use Default Parameter Values in TypeScript?
I’m Bijay Kumar Sahoo, and I am honored to be awarded the Microsoft MVP. With over 18 years of experience in the IT industry, I got a chance to work on SharePoint Framework (SPFx) development, TypeScript, React, JavaScript, etc. My journey has taken me through esteemed organizations such as TCS, HP, and KPIT, where I have honed my skills and expanded my expertise. Check out more about me here.