Hell Week
Hell Week is the fourth week of First Phase at BUD/S, the five-and-a-half-day stretch the Navy calls the course's crucible event. A class goes into it after three weeks of increasingly hard physical evolutions and comes out of it either still in the class or gone from the pipeline.
Where Hell Week Falls
BUD/S runs 21 weeks in three seven-week phases, and Hell Week takes the fourth week of the first of them. Naval Special Warfare's instruction for the assessment and selection programme lists it as one of First Phase's three test gates, the events a candidate has to clear to stay in the class. The Navy's own investigation into BUD/S Class 352 (Naval Education and Training Command, 24 March 2023) splits First Phase into three parts: three weeks of progressively harder evolutions, week four as Hell Week, then three weeks that open with recovery and rehabilitation before the testable events return.
What the Week Costs
The numbers are official, not folklore. Naval Special Warfare Command's caption for its own Hell Week photograph reads five and a half days in which each candidate sleeps about four total hours, runs more than 200 miles, and does more than 20 hours of physical training a day. The 2023 command investigation counts over 26 individual evolutions across 108.5 hours and describes the week as a crucible event built to expose candidates to extreme stress in a controlled environment: continuous physical effort, training in harsh environments, and sleep deprivation. Medical cover is part of the week; the class is not left to fend for itself.
What Happens After Hell Week
Finishing the week is the gate First Phase is built around. The three weeks that follow begin with recovery and rehabilitation, then add mentorship sessions and academic work, and bring the graded swims, runs and obstacle course work back as candidates recover. A candidate who drops on request, or is pulled from the class, during Hell Week is seen by a psychologist and spends the next 24 hours in the Recovery Observation Center, observed by an instructor and a medical professional since 2020.
Train for the tired version of yourself. A long session on too little sleep tells you more about Hell Week than a fresh one ever will.
Related Terms
First Phase is the seven-week opening block of BUD/S, the phase that selects and prepares candidates physically and psychologically for the rest of the pipeline. It holds Hell Week, and it is where most of a BUD/S class is lost.
BUD/S orientation, which the Navy calls Naval Special Warfare Orientation (NSWO), is the seven-week course candidates complete before BUD/S begins. The Navy describes its purpose as building the conditioning base and the water competency that the pipeline then demands.
A Drop on Request (DOR) is a BUD/S candidate's own request to leave training. The Navy requires it to be said out loud and then put in writing, and the process is explained to candidates during orientation and again before evolutions.
BUD/S (Basic Underwater Demolition/SEAL) preparation refers to the structured physical training undertaken before entering the Navy SEAL selection pipeline. The Naval Special Warfare Physical Training Guide outlines a 26-week progressive program designed to build the endurance, strength, and mental resilience required to attempt BUD/S.
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