That brass plate on the front of your Mills slot machine isn't just for show. If you've inherited an old mechanical slot or found one at an estate sale, the serial number stamped on that plate is the difference between having a $500 conversation piece and a $3,000 collector's item. The problem? Mills produced millions of these machines over nearly a century, and figuring out exactly what you're looking at can be incredibly frustrating without the right reference points.
Mills Novelty Company slot machines were the backbone of American gambling from the 1890s through the 1950s. They built everything from the iconic Liberty Bell replicas to the elaborate console models that sat in high-end cigar shops. Understanding their serial number system helps you date your machine, confirm authenticity, and spot the reproductions that flooded the market in the 1970s and 80s.
Where to Find Serial Numbers on Mills Machines
Before you can decode anything, you need to find the number. On most Mills machines, the primary serial number location is on a brass plate riveted to the front casting, usually near the coin entry or below the reel window. On antique slot machines from the early 1900s, look for the number stamped directly into the cast iron mech frame inside the cabinet.
The castings sometimes have different numbers than the mechanism itself, which confuses new collectors. The serial on the mechanism is the one that matters for dating. Front casting numbers were sometimes changed when operators rebuilt machines or swapped cabinets. If you open the side door and find a different number stamped into the internal mechanism, that internal number is your true identifier.
Some models, particularly the Mills High Top and Bursting Cherry models from the 1940s and 50s, have the serial number on a small metal tag attached to the inside of the cabinet door. Check the bottom edge of the inside frame as well - Mills sometimes stamped numbers there on floor model machines.
Dating Mills Slot Machines by Serial Number Ranges
Mills didn't publish official serial number lists, which makes precise dating difficult. However, collectors have reverse-engineered approximate ranges by cross-referencing known machines with patent dates, mechanical features, and historical records.
Machines with serial numbers in the 1-50,000 range typically predate 1910. These are the early upright cabinet models and Liberty Bell derivatives. If you have a machine in this range with original mech and castings, you're holding a legitimate antique. Numbers from 50,000 to 500,000 span roughly 1910 to 1935, covering the height of the Mills Golden Age when they produced the War Eagle, Roman Head, and Lion Head models.
The 500,000 to 1,000,000 range covers the Depression era through the early 1950s, including the popular Mills High Top and various console models. Numbers above one million are usually post-1955 machines or reissues. If you see a machine claiming to be vintage but with a seven-digit serial starting with 2 or higher, approach with caution - it might be a reproduction.
Identifying Counterfeits and Reproduction Machines
This is where knowing your serial numbers actually protects your wallet. In the 1970s and 80s, companies produced thousands of reproduction Mills machines, primarily copies of the Liberty Bell and early upright models. These were sold as decorative items but often find their way onto the secondary market presented as originals.
Authentic Mills machines have serial numbers stamped with consistent font and depth. Reproductions often have numbers that look laser-etched or cast into the plate rather than stamped. The brass plates on originals develop natural patina and oxidation around the edges; reproduction plates often look too clean or artificially aged.
Check the patent dates on the award card or inside the mech. If the patent dates are from the 1970s or later, you're looking at a reproduction regardless of what the serial plate claims. Real Mills machines won't have patent dates that postdate the company's operations. Mills Novelty Company was sold and reorganized several times, but their classic mechanical slot production effectively ended by the mid-1960s.
Model Variations and Serial Number Patterns
Different Mills models have distinct serial number conventions. The Mills High Top, probably the most common model collectors encounter today, typically has serials in the 400,000 to 800,000 range. These machines were produced from roughly 1947 to 1958, and genuine examples should have matching serials on the cash box door, inner door frame, and mechanism frame.
Mills console slots from the 1940s - the quarter-eating machines designed for cigar stores and bars - have their own numbering sequences. These machines are considerably rarer than the countertop models, and serial numbers often include letter prefixes indicating the specific model designation. A Bell Console might have a "BC" prefix, while a Jackpot Console uses "JC."
The earlier 1930s models like the War Eagle and Golden Nugget have serials in the 200,000 to 400,000 range. These machines are immediately identifiable by their ornate castings with Native American and gold rush themes. If someone offers you a "War Eagle" with a serial number above one million, something doesn't add up.
Why Serial Numbers Matter for Value and Legality
Beyond authentication, serial numbers determine value. Collectors pay premiums for machines with documented provenance or serials that place the machine in a historically significant range. Machines verifiably produced before 1940 generally command higher prices than post-war models, and pre-1920 machines in working condition are legitimate investment-grade antiques.
The legal situation varies by state. Some states exempt machines over 25 or 40 years old from gambling device restrictions, making accurate dating essential for owners. A machine from the 1920s might be legal to own while an identical-looking reproduction from the 1980s isn't. Serial number documentation can be the difference between a legitimate antique and a prohibited device.
For insurance purposes, you need serial numbers. Standard homeowner's policies often don't cover collectibles adequately, and appraisers require serial documentation for accurate valuations. If your Mills machine is ever stolen, having the serial number recorded gives you a chance of recovery. These machines are portable and frequently targeted by thieves who know exactly what they're taking.
Registration and Collector Resources
Serious collectors register their machines with organizations like the Coin Machine Register or specialized slot machine collector associations. This creates a paper trail linking serial numbers to ownership history, which helps with both authentication and resale value. When you eventually sell a documented machine, that registration history gives buyers confidence they're getting the real thing.
Several reference books compile known serial number ranges, though none are detailed. The "Slot Machine Serial Number Index" published by various collector groups represents decades of crowd-sourced data. Online collector forums maintain running databases where owners can compare notes and help date unusual machines.
FAQ
How do I look up a Mills slot machine serial number?
There's no official Mills database, but you can reference collector-published serial number indexes that compile known ranges. Post clear photos of your serial plate on collector forums like Antique Slot Machine Enthusiasts or Slot Machine Forum - experienced collectors can often narrow down the production decade based on font style, plate design, and number sequence.
Where is the serial number on a Mills High Top slot machine?
Check the brass plate on the front casting below the reel window first. The internal mechanism frame inside the side cabinet door should have a matching or related number. On High Top models, also check the cash box door frame - legitimate machines usually have the same serial stamped in multiple locations.
Are old Mills slot machines legal to own?
It depends entirely on your state and the machine's age. Many states exempt machines over 25 years old from gambling device prohibitions. Others require them to be permanently disabled or used only for display. California, Nevada, and several other states allow ownership of qualifying antique slots with proper registration. Check your local laws before purchasing.
What is my Mills slot machine worth?
Values range from a few hundred dollars for non-working post-war models to over $10,000 for rare pre-1930 machines in original condition. Serial numbers that verify early production dates increase value significantly. Working mechanisms, original paint, and documented provenance all boost price. Reproduction machines from the 1970s onward typically sell for $300-600 regardless of cosmetic condition.
How can I tell if my Mills slot machine is a reproduction?
Check the patent dates on internal components - authentic Mills machines won't have patent dates from the 1970s or later. Look at the serial plate stamping: original stamping has consistent depth and vintage font, while reproductions often show laser etching or cast-in numbers. Reproductions also tend to have hardware like Phillips head screws, which weren't used in the Mills production era.