- What Is USPS Maintenance Exam 955?
- Who Administers It - And Why It's Free
- Exam Format: Multicraft and Spatial Relations
- The 9 Content Domains Explained
- How Scoring, Passing, and Veterans' Preference Work
- Retest Rules Under Handbook EL-304
- What Jobs Exam 955 Actually Fills
- Who Can Take It
- Preparing Around the Real Exam Structure
- Frequently Asked Questions
- USPS 955 is administered directly by USPS under Handbook EL-304 - no fee, no third-party vendor.
- It has exactly two parts: Multicraft (60 items/60 minutes) and Spatial Relations (68 items/40 minutes).
- A minimum score of 70 is required just to be considered; ratings run 70 to 100.
- There is no Personal Characteristics and Experience Inventory - that belonged to the retired Exam 473.
What Is USPS Maintenance Exam 955?
USPS Maintenance Exam 955 is the assessment the United States Postal Service uses to fill skilled maintenance craft positions through its Maintenance Selection System. It is not a certification you earn once and carry from employer to employer - it is a job-specific entrance and in-service exam tied directly to USPS hiring under Handbook EL-304. If you're researching this topic for the first time, this overview pairs well with our companion piece on USPS 955 Meaning and the broader breakdown of what USPS 955 stands for.
The exam evaluates whether a candidate has the mechanical, electrical, and spatial-reasoning aptitude required to maintain the automated equipment, building systems, and vehicles that keep postal operations running. Because several unrelated credentials share the "955" label elsewhere online, it's worth being precise: everything in this article refers exclusively to the USPS Maintenance Selection System exam, not any other program.
Who Administers It - And Why It's Free
Exam 955 is administered by USPS itself at approved test centers, not by a commercial testing company. It is proctored and computer-delivered, and candidates must bring valid photo identification to sit for it. There is no cost to take the exam - USPS is explicit that it never charges for exams, applications, or employment information, and the Postal Inspection Service treats any request for payment tied to the exam as an employment scam.
This matters for anyone researching the exam online, because scam listings and misleading "certification" sites sometimes imply otherwise. If cost or pricing structure is your main question, our dedicated page on USPS 955 Certification Cost breaks this down in more detail.
Exam Format: Multicraft and Spatial Relations
The official USPS Assessment Information Package defines exactly two parts to Exam 955, totaling roughly two hours of testing time:
- Multicraft: 60 items, 60 minutes. This section assesses mechanical and electrical job skills relevant to the maintenance craft.
- Spatial Relations: 68 items, 40 minutes. This section is split into two item types - Matching Parts and Figures, where you determine which figure shows how loose pieces fit together without gaps or overlap, and Spatial Visualization, where you determine which solid would produce a given set of top, front, and right views.
Key Takeaway
There is no essay, no personality inventory, and no experience questionnaire on Exam 955 - just two timed, objective sections built around mechanical/electrical knowledge and spatial reasoning.
One persistent point of confusion is worth flagging directly: some study guides still describe a Personal Characteristics and Experience Inventory component. That inventory belonged to the retired Exam 473, an entirely different postal assessment, and it is not part of Exam 955. If you encounter prep material referencing it, that material is outdated or mismatched to the wrong exam.
The 9 Content Domains Explained
Exam content is drawn from 21 technical fields covering roughly 131 topics, blending practical craft knowledge with the underlying scientific theory behind it. USPS groups this content conceptually into nine domains that candidates should know going into test day. For a deeper walkthrough of each one, see our full USPS 955 Exam Domains Guide.
Domain 1: AC/DC Theory, Power Distribution, and Electrical Maintenance
Covers fundamental circuit theory, how power is distributed through facility systems, and troubleshooting electrical maintenance issues.
- Ohm's Law and circuit fundamentals
- Distribution panels and wiring systems
Domain 2: Motors, Control Circuits, Schematics, and Print Reading
Focuses on how motors and control circuits operate and how to interpret schematics and technical prints used in maintenance work.
- Reading wiring diagrams accurately under time pressure
- Motor control logic and sequencing
Domain 3: Digital Electronics, Power Supplies, Computers, and Test Instruments
Tests familiarity with digital logic, power supply function, computer-based control systems, and the instruments used to test them.
- Multimeter and test equipment use
- Basic digital logic concepts
Domain 4: Hydraulics and Pneumatics
Covers fluid power systems, including how hydraulic and pneumatic components generate and transmit force in mechanical systems.
- Cylinders, valves, and actuators
- Pressure and flow relationships
Domain 5: Pumps, Piping and Combustion
Focuses on pump types, piping systems, and combustion principles relevant to facility maintenance equipment.
- Pump operation and common failure points
- Piping layout and combustion basics
Domain 6: Power Transmission, Lubrication, Mechanical Maintenance, and Shop Machines, Tools and Equipment
A broad practical domain covering belts, gears, bearings, lubrication schedules, and the shop tools used in day-to-day mechanical upkeep.
- Lubrication types and intervals
- Proper use of common shop tools
Domain 7: Welding and Rigging
Covers welding fundamentals and rigging safety and technique used when moving or securing heavy equipment.
- Weld types and appropriate applications
- Rigging load and safety principles
Domain 8: Spatial Relations - Matching Parts and Figures
Directly matches the Matching Parts and Figures portion of the Spatial Relations section on the exam itself.
- Visualizing how loose pieces combine without gaps or overlap
Domain 9: Spatial Relations - Spatial Visualization
Directly matches the Spatial Visualization portion, requiring you to mentally rotate and reconstruct 3D solids from 2D views.
- Interpreting top, front, and right view combinations
Note that USPS does not publish a percentage weighting per knowledge area - performance is reported only in High, Average, and Low bands per content area, so treat domain study time as directional rather than tied to a fixed scoring formula.
How Scoring, Passing, and Veterans' Preference Work
To be considered for any position applied for, a candidate needs a minimum score of 70, excluding Veterans' Preference points. Eligible ratings run from 70 to 100. Veterans' Preference points are added only after a candidate has already achieved a passing score - they cannot turn a failing result into an eligible one. For the full mechanics of scoring, see USPS 955 Passing Score.
| Score Element | Rule |
|---|---|
| Minimum passing score | 70 (excluding Veterans' Preference) |
| Eligible rating range | 70 to 100 |
| Veterans' Preference points | Added only to already-passing scores |
| Content-area reporting | High, Average, Low bands only - no percentage breakdown |
Retest Rules Under Handbook EL-304
Handbook EL-304 sets a 120-day rule for retesting. Entrance applicants who reapply may retake the exam, or reuse their existing score, once 120 days or more have passed since their original test date. Incraft candidates testing for a score update may reschedule 120 days after their original exam date as well.
Score validity differs depending on applicant type: entrance ratings carry an expiration date printed directly on the Notice of Results, while inservice scores remain valid indefinitely unless examination requirements change. If you're mapping out timing around application windows, our guide to USPS 955 Exam Dates covers scheduling considerations in more depth.
What Jobs Exam 955 Actually Fills
The Maintenance Selection System uses Exam 955 to fill a specific set of skilled craft positions, including:
- Electronic Technician PS-10 and PS-11
- Maintenance Mechanic MPE
- Area Maintenance Specialist
- Building Equipment Mechanic
- Maintenance Electrician
- Machinist
- Carpenter
- Mason
- Plumber
- Painter
- Blacksmith-Welder
- Letter Box Mechanic
- Building Maintenance Custodian
Because the domains map so directly onto real craft responsibilities - electrical theory for electricians, welding and rigging content for blacksmith-welders, hydraulics for mechanics - the exam functions more like a skills screen than a generic aptitude test. For a role-by-role look at where this leads, browse USPS 955 Jobs.
Who Can Take It
There are no formal education prerequisites to sit for Exam 955. It's open to two groups: external entrance applicants applying to USPS from outside the organization, and current employees testing during the Maintenance Craft in-service open season. Full eligibility mechanics, including how the two applicant paths differ, are covered in USPS 955 Requirements.
Preparing Around the Real Exam Structure
Because Multicraft and Spatial Relations test very different skill types, most candidates benefit from separating study time by section rather than mixing everything together. A simple way to structure preparation is to dedicate early weeks to the technical domains (1 through 7) that feed Multicraft, then shift toward timed Spatial Relations practice (domains 8 and 9) as test day approaches, since spatial reasoning speed tends to improve with focused repetition close to the exam date.
Electrical & Electronic Foundations
- Review Domain 1 (AC/DC theory) and Domain 2 (motors, schematics)
- Practice reading control circuit diagrams
Digital, Fluid Power, and Mechanical Systems
- Work through Domain 3 (digital electronics, test instruments)
- Cover Domains 4-6 (hydraulics, pumps/piping, mechanical maintenance)
Welding, Rigging, and Review
- Study Domain 7 fundamentals
- Revisit weak technical areas identified in practice sessions
Timed Spatial Relations Drilling
- Practice Matching Parts and Figures under time pressure
- Drill Spatial Visualization with top/front/right view exercises
If you want a structured walkthrough rather than building your own plan from scratch, our full USPS 955 Study Guide lays out a complete first-attempt strategy, and you can gauge realistic difficulty expectations in How Hard Is the USPS 955 Exam?. Timed practice sessions on our practice test platform are especially useful for the Spatial Relations section, since speed under a strict 40-minute limit is often the deciding factor between a passing and non-passing score.
Key Takeaway
Don't split study time evenly across all nine domains - weight early prep toward the technical Multicraft domains, then concentrate on timed drilling for Spatial Relations as your exam date nears.
For candidates weighing whether the effort is worthwhile relative to the craft positions it unlocks, Is the USPS 955 Certification Worth It? and the USPS 955 Salary Guide offer additional context, while a quick-reference summary of core facts is available in the USPS 955 Cheat Sheet. You can also start reviewing sample questions right away on the main practice test site.
Frequently Asked Questions
No. USPS charges no fee for the exam, application, or employment information, and treats any request for payment as a scam.
Exactly two: Multicraft (60 items, 60 minutes) and Spatial Relations (68 items, 40 minutes), which itself splits into Matching Parts and Figures and Spatial Visualization.
No. That component, the Personal Characteristics and Experience Inventory, belonged to the retired Exam 473 and is not part of Exam 955, despite some outdated guides claiming otherwise.
A minimum score of 70, excluding Veterans' Preference points, is required to be considered for any position, with eligible ratings ranging from 70 to 100.
Handbook EL-304 sets a 120-day rule: entrance applicants can retest or reuse their score 120 days or more after their original test, and inservice candidates seeking a score update follow the same 120-day window.