Yes, for the vast majority of people, retiring at 55 with $4 million and no debt is an incredibly secure position. A conservative application of the 4% withdrawal rule would provide an annual income of $160,000, which is sufficient for a comfortable, or even luxurious, lifestyle in most places, especially without the burden of mortgage or other loan payments. This considerable nest egg offers significant financial stability and flexibility, allowing for travel, pursuing hobbies, and weathering unexpected financial challenges. Of course, individual spending habits and the desired level of luxury still play a role, but with proper planning, $4 million provides a solid foundation for a long and enjoyable retirement.