Every Kubota tractor has a model number that tells you exactly what it is — if you know how to read it. The letters tell you the size class. The first two digits tell you the horsepower. The last two digits tell you which generation and chassis family. The letters after that tell you the transmission and drive configuration. Once you know the system, you can decode any Kubota model number in seconds — and spot immediately when something doesn’t add up on a used tractor listing.

How the Kubota Naming System Works

Kubota compact and utility tractors follow a consistent three-part naming structure: series letters that define size class, a two-digit number that approximates engine horsepower, a two-digit family code that identifies the chassis generation, and suffix letters that describe transmission type and drive configuration. Understanding these four components lets you decode any current Kubota model instantly — and gives you important context when shopping used.

The system evolved from simpler older naming conventions. Early Kubota models like the L185, L245, and B7100 used shorter numbers with looser HP correlation. Modern models like the L3301, B2601, and MX5400 follow the clean formula consistently. When you encounter an older model number that doesn’t fit the pattern, it’s almost certainly a pre-2000s machine or a gray-market import.

Series Letter Prefixes — What Each Letter Means

The letters at the beginning of every Kubota model number are the most important part. They tell you the size class, the chassis type, and the intended use before you even look at the numbers.

BX Series — Sub-Subcompact

The BX is Kubota’s smallest tractor line — roughly 18-26 HP, with a very low profile chassis designed around mid-mount mower use. The “X” indicates a smaller version of the B line. BX tractors have less ground clearance than B series, a more compact footprint, and are optimized for residential mowing, light loader work, and tight spaces. They are not interchangeable with B series despite overlapping HP ranges — the chassis, loader capacity, and ground clearance are meaningfully different.

B Series — Compact

The B series are small compact tractors in the 18-30 HP range with more ground clearance and heavier chassis than BX. They’re estate and homeowner focused but capable of real ground-engaging implement work that the BX struggles with. Current B series models use the “01” family code (B2301, B2601) and replaced older families like the B2620 and B2650.

L Series — Mid-Size Compact

The L series covers roughly 25-60 HP and is Kubota’s most popular compact tractor line. L series tractors have significantly heavier frames than B and BX and broad implement support. The current L line splits into two families: Standard L (family code “01” — L2501, L3301, L3901, L4701) and Grand L (family code “60” — L3560, L4060, L4760), which has more premium features and a heavier chassis. Same “L” prefix, very different tractors.

LX Series — Premium Compact

The LX series sits between B and L in size but above both in features. LX tractors (26-35 HP, family code “10” — LX2610, LX3310) emphasize comfort, cab availability, and versatility for property owners who want a more refined experience than the Standard L provides. LX is often confused with L — they’re related but the LX is a premium compact, not a heavier-duty workhorse.

MX Series — Mid-Frame Value

The MX series fills the gap between the L and M series at roughly 50-60 HP. The “X” again signals a smaller, more value-oriented version of the M line. MX tractors use a lighter chassis than comparable M models and currently carry the “00” family code (MX5400, MX6000). They’re popular for hay work, loader use, and small farm operations where a full M series is overkill.

M Series — Utility and Row Crop

The M series are Kubota’s utility and row-crop tractors, ranging from roughly 40 to 135+ HP. Within M you’ll see families designated by codes like “60” (M7060), “X,” and “GX” that indicate different chassis and feature levels. M series tractors have heavier axles, higher hydraulic capacity, and more agricultural-oriented options than anything in the compact lines.

Other Prefixes

The T series are lawn and garden tractors — lighter, residential mowing machines generally under 20 HP. The Z series are zero-turn mowers (ZD for diesel, ZG for gas), where numbers indicate deck size and performance class. The R series appears on Kubota wheel loaders and industrial equipment rather than tractors. SVL and SSL designate skid steers and track loaders. All follow the same general logic: letters define the product line, numbers indicate size class.

Current Kubota Series — Quick Reference

The Number Component — HP Digits and Family Code

First Two Digits = Approximate HP

The first two digits of the number in any modern Kubota model correspond to approximate engine horsepower. An L3301 is about 33 HP. A B2601 is about 26 HP. An MX5400 is about 54 HP. An M7060 is about 70 HP. This is engine gross HP, not PTO HP — PTO horsepower is always lower. The relationship is approximate, not exact: a “33” model might spec at 32.2 or 33.5 HP depending on emissions tuning and rating standards. Treat it as a ballpark size indicator, not a precise specification.

Last Two Digits = Family/Generation Code

The last two digits are not HP, not model year, and not a ranking. They identify which chassis family and generation the tractor belongs to. This is where most buyers get confused. Common current family codes:

Suffix Letters — Transmission, Drive, and Options

The letters that come after the number are critical for understanding what you’re actually buying. Two tractors with the same base model number can be completely different machines depending on their suffixes.

Transmission Suffixes

HST means hydrostatic transmission — foot pedal controlled, infinite speed range within 2-3 gear ranges. This is the most common transmission on BX, B, L, LX, and MX series and the most popular choice for property owners. HSD (or HST-D) means hydrostatic transmission with 4WD — the “D” effectively means dual drive. Many compact models default to 4WD with HST so you’ll see HSD frequently on B and LX series. DT means gear drive with mechanical shuttle, typically 4WD — “Dual Traction” in common dealer usage. You’ll see DT on L and M series gear models. F means 2WD gear drive — an L3301F is a 2WD gear transmission version of the L3301. GST means Glide Shift Transmission, Kubota’s clutchless power-shift style gearbox used on older Grand L and M series models.

Other Common Suffixes

CAB or C indicates a factory cab — often written as “HSTC” or “HDC” in model designations (L4060HSTC for example). S in BX23S means the specialized TLB (tractor-loader-backhoe) package with an integrated subframe backhoe — it’s not just a BX with a backhoe bolted on, it’s a dedicated TLB platform. LA followed by numbers (LA344, LA435, LA525) refers to the loader model, not the tractor — these are separate implement designations that get written alongside the tractor model in listings.

Fully Decoded — 9 Common Kubota Models

BX2380

BX23S

B2601

L2501

L3301 HST

L3560

LX3310

MX5400

M7060

Serial Numbers — How to Find Build Date and Verify Your Tractor

Where Serial Numbers Are Located

On most B, L, and M series tractors the serial plate is on the forward end of the transmission case — left or right side depending on model. Kubota also places a sticker on the right front of the tractor frame with the same number. If the sticker is missing, the stamped transmission case number is the fallback. Engine serial numbers are separate — stamped on the engine block itself, typically on the right side near the injection pump — and follow a different numbering system than the tractor serial.

The 17-Digit Serial Number System

Modern Kubota tractors use a 17-digit alphanumeric serial number. The first three characters (often “KBU”) identify the Kubota compact tractor engineering division. Later digits encode the series, internal project identifier, and production details. Most importantly, digits 10 and 12 encode the build year and build month — a dealer with the decoding chart can tell you the exact production month and year from these positions. Note that Kubota considers “model year” the year of first retail sale, not the production year, so a tractor built in October might be sold as the following model year.

Using Serial Number to Verify Build Date

For older engines built before May 2012, a 6-digit engine serial uses the first digit for production year and the second for production month. Later engines use a 7-digit code where digits 2-3 indicate year and digit 4 indicates month. For the newer 17-digit tractor serials, your Kubota dealer can decode the exact build date by serial number — always ask them to print this verification when buying used rather than trusting seller claims about model year.

Older and Discontinued Model Numbers

Older Kubota models predate the clean HP + family code system. Early L series like the L185, L225, and L245 used three-digit numbers where the first two digits loosely correlated to HP but without the consistent two-digit family code. Classic B series like the B6100, B7100, and B8200 used three or four-digit numbers that indicated frame and HP class but not with the precision of modern naming. Early M series like the M4050 and M5030 followed similar logic — M5030 was roughly 50 HP class — without the current “60/X/GX” family identifiers.

As a quick era guide: simple two or three-digit L numbers (L185, L245) and three or four-digit B numbers (B7100, B8200) are typically 1970s-1990s machines. Models like L2800, L3400, and L4400 are early 2000s transitional compacts using a “00” family prior to the L01 generation. Grand L30 and L40 series (L3130, L3430, L3540) are 2000s to early 2010s predecessors to the current L60 Grand L family.

Common Model Number Confusion — and How to Avoid It

BX vs B — Not the Same Tractor

The BX2380 and B2301 have similar HP on paper but very different chassis. BX tractors are lower, smaller-framed, and mower-centric. B tractors are taller, heavier, and better for ground-engaging implement work. Many buyers see overlapping HP ranges and assume they’re interchangeable — they’re not. The loader capacities, ground clearance, and 3-point lift ratings are meaningfully different.

L vs LX — Features vs Capability

LX models are premium compacts between B and L that emphasize comfort and cab availability. Standard L tractors are heavier-duty workhorses. A buyer wanting a nicer cab experience often gravitates toward LX. A buyer wanting maximum raw capability per HP often lands on Standard L. Both are excellent tractors for different priorities.

The Family Code Is Not HP or Year

The most common number misread: seeing the last two digits as horsepower or model year. An L3560 is not 60 HP — it’s 35 HP in the Grand L “60” family. An M7060 built in 2019 has “60” in the model name not because of its year but because it’s in the M-60 chassis family. Always split the four-digit number: first two = HP, last two = family code.

Missing Suffix = Missing Critical Information

A used listing that says “L3301” without a suffix is incomplete. That same base model number covers an L3301F (2WD gear), L3301DT (4WD gear), and L3301HST (hydrostatic). These are mechanically different tractors with different price points and different feels to operate. Always confirm the full model designation including suffix before evaluating any used tractor listing.

Dealer Shorthand

Dealers frequently abbreviate in conversation — “the 23S,” “a 33 hydro,” “the 7060 cab.” These refer to the BX23S, L3301HST, and M7060 with cab respectively. New buyers who don’t yet know the full model naming system can misinterpret these shorthands as different models entirely. When in doubt, always ask for the complete model designation and write it down.

Frequently Asked Questions

The Formula in 10 Seconds

Related Guides

• Kubota BX vs B vs L Series: Which Size Should You Buy?
• Kubota BX vs B Series: Full Comparison
• Kubota BX1880 vs BX2380 vs BX2680: Which BX80 Should You Buy?
• Kubota BX23S vs BX2380: TLB or Loader-Only?
• Kubota B2601 vs B2650: Which B-Series is Right for You?
• Used Kubota Tractor Inspection Guide: Don’t Buy Without This
• Kubota L2501 vs John Deere 1025R: Full Comparison
• Kubota Tractor Maintenance Ultimate Checklist
• Best Kubota Tractors for Small Farms: 2026 Guide
• Best Implements for New Kubota Owners: 2026 Guide