Swine Ear Notching Laws in Pennsylvania: What Every Hog Producer Needs to Know
July 12, 2026
If you raise hogs in Pennsylvania — whether on a small family farm, a registered purebred operation, or as a 4-H project — swine identification rules affect you more than you might expect. Ear notching has been a cornerstone of hog identification for generations, but Pennsylvania’s regulatory landscape layers state code, USDA-APHIS requirements, and exhibition mandates on top of the traditional notching practice.
Understanding exactly when ear notching counts as official identification, when it does not, and how it stacks up against RFID tags and tattoos will keep your operation compliant and your animals traceable. This guide walks through every layer of Pennsylvania’s swine identification framework so you know precisely what is required of you.
Pro Tip: Before moving any swine within or out of Pennsylvania, confirm identification requirements with the Pennsylvania Department of Agriculture’s Bureau of Animal Health and Diagnostic Services. Rules can change, and your State Animal Health Official is the definitive authority for your specific situation.
What Is Swine Ear Notching and When It Is Used in Pennsylvania
Swine ear notching is a permanent identification method in which small V-shaped cuts are made in specific positions on a piglet’s ears. Each position carries a numeric value, and the combination of notches encodes both the litter number and the individual pig’s number within that litter. Unlike ear tags, which can fall out, or tattoos, which require ink and a separate tool, notching creates a lifelong mark directly in the cartilage of the ear.
On Pennsylvania farms, notching is most commonly performed within the first 24 to 48 hours of a piglet’s life, when the cartilage is still soft and the procedure causes minimal stress. Most piglets are notched within 24 hours of birth, which also helps producers keep accurate records when multiple sows may be farrowing around the same time. Ear notches help breeders maintain accurate records for registration and health records on the farm, including vaccination records.
In Pennsylvania, ear notching is used primarily in two contexts: purebred herd management and show pig identification. Commercial producers raising market hogs for slaughter have largely shifted to premises-based ear tags and RFID technology, but registered breed operations continue to rely on notching as the backbone of their record-keeping system. If you raise Durocs, Hampshires, Landrace, or Yorkshires for registry purposes, ear notching is not optional — it is the required identification method for those registrations.
When Ear Notching Qualifies as Official Identification in Pennsylvania
Not every notched pig carries “official” identification in the regulatory sense. Pennsylvania law and USDA-APHIS rules draw a clear line between a management tool and a legally recognized ID method. Knowing which side of that line your animals fall on matters whenever you move, sell, or exhibit hogs.
APHIS-approved means of swine identification include official eartags, USDA backtags only when used on swine moving in slaughter channels, official swine tattoos on swine moving in slaughter channels, and ear notching — but only if the ear notching has been recorded in the book of record of a purebred registry association. That last qualifier is the critical one for Pennsylvania producers: a notch alone does not make your pig officially identified. The notch must be documented with a recognized registry.
Pennsylvania’s own health certificate regulations reinforce this framework. A Pennsylvania health certificate (AAI-13) is used to certify that health requirements have been met for transportation of animals within the Commonwealth or in interstate commerce, and must include an accurate description of the animal including complete identification — ear tag, tattoo, brand, registration number, ear notches, or other designations. Ear notches are explicitly listed as an acceptable identifier on the AAI-13 form, but they must be legible and, for official purposes, traceable to registry records.
Important Note: If you are moving non-registered commercial hogs within or out of Pennsylvania, ear notches alone will not satisfy official identification requirements. Those animals need an eartag or tattoo bearing a Premises Identification Number (PIN) issued by the Pennsylvania Department of Agriculture.
How the 1-3-9 Ear Notching System Works
The universal swine ear notching system used across Pennsylvania and the rest of the United States follows a positional numeric code built around the values 1, 3, 9, 27, and 81. Once you understand the logic, reading a pig’s ear notches becomes straightforward — and you can decode any pig’s litter and individual number at a glance.
Each ear is divided into four quadrants, and each quadrant represents a number. The outside bottom quadrant represents 1; if there are two notches in that quadrant, the number is 1+1, or 2. There will never be more than two notches in any quadrant. The outside top quadrant represents 3, and the inside top quadrant represents 9. In the litter ear only, the inside bottom represents 27. The notch in the very tip of the right ear signifies litter number 81.
The two ears serve different purposes. The right ear is used for the litter mark, and all pigs in the same litter must have the same notches in the right ear. The left ear identifies individual pigs in the same litter, and all littermates must have different notches in the left ear, with no more than two notches at any position.
To read a pig’s identity, you add up the values of all notched positions in each ear. After notching, an individual pig’s identification would be read as something like 14-6, where 14 represents a pig from the 14th litter and 6 represents the 6th pig within that litter. A practical example: a pig with the ear notch of 33-7 would have two notches in the “3” location on the left ear and one notch in the “1” location (3+3+1=7), while in the right ear, one notch in the “27” region and two notches in the “3” region (27+3+3=33).
| Ear | Purpose | Zones Available | Maximum Notches per Zone |
|---|---|---|---|
| Right Ear | Litter number | 1, 3, 9, 27, 81 (tip) | 2 (except 81 tip: 1 only) |
| Left Ear | Individual pig number | 1, 3, 9 | 2 per zone |
There are five designated zones (1, 3, 9, 27, and 81) in the litter ear and three designated zones (1, 3, and 9) in the individual pig ear. In zones 1, 3, 9, and 27, there can only be two notches — meaning two notches in all four zones represents litter 80. A notch in zone 81 then doubles the system. This design lets producers track well over 100 litters without repeating a combination, making it practical even on larger Pennsylvania hog farms.
A helpful memory tip from Penn State Extension’s swine home study course: since confusion over which ear is the “left ear” can easily occur depending on whether you view the pig from the front or rear, always look the pig in the face — reading left to right will always give you litter number first, then pig number.
Ear Notching for Purebred Registry Compliance in Pennsylvania
If you are raising registered purebred hogs in Pennsylvania, ear notching is not just a management preference — it is a condition of registration with the major breed associations. The National Swine Registry (NSR), which covers Duroc, Hampshire, Landrace, and Yorkshire breeds, and Certified Pedigreed Swine (CPS) both require the universal ear notching system for pigs submitted for registration.
The universal ear notching system must be used to identify purebred hogs submitted for registration with the National Swine Registry. When you submit a registration application, the ear notch code you record must match the notches physically present on the animal. Discrepancies can delay or void registration, which creates problems when you go to sell breeding stock or show animals at Pennsylvania county fairs and state exhibitions.
January 1 and July 1 of each year are the starts of each farrowing season for CPS registry purposes, which affects how litter numbers are assigned and recorded. If you farrow sows across both halves of the year, you need to restart your litter numbering sequence accordingly to stay aligned with registry requirements.
The registry connection is also what elevates ear notching to official USDA identification status. Ear notching qualifies as official identification if the ear notching has been recorded in the book of record of a purebred registry association. Without that registry record, the notch is a farm management tool, not a legal identifier for interstate movement purposes. Pennsylvania purebred producers should keep registration certificates on file and accessible whenever registered animals are transported, shown, or sold.
Pro Tip: When selling registered piglets, transfer the registration paperwork to the buyer at the time of sale. The buyer’s ability to use ear notching as official ID depends on having documentation that ties the notch code to the registry’s book of record.
Pennsylvania also has a robust 4-H swine program, and junior members showing registered animals at county fairs need to understand that their pig’s ear notch must be correctly recorded on all enrollment and health paperwork. Errors in transcribing the litter or pig number are among the most common compliance issues for youth exhibitors in the Commonwealth. For related livestock ownership rules in the state, you may also want to review goat ownership laws in Pennsylvania, which covers comparable ID and movement requirements for another common livestock species.
Ear Notching vs. Ear Tags, Tattoos, and RFID in Pennsylvania
Pennsylvania producers have several identification tools available, and the right choice depends on your operation type, whether your animals are destined for exhibition or slaughter, and whether they will cross state lines. Each method has specific regulatory standing under both Pennsylvania and federal rules.
RFID Tags (840 Tags)
For show pigs in Pennsylvania, RFID has become the dominant official identification method. In 2016, the Pennsylvania Department of Agriculture mandated that all show pigs must have RFID (Radio Frequency Identification) tags in their ears, and the RFID tag should start with the numbers 840. This requirement applies regardless of whether the animal also carries ear notches. If the pig already has an 840 RFID tag in its ear, that is the tag that must be used to identify the animal; if your fair is supplying 840 RFID tags and your animal already has one from the breeder, the fair must use the one placed by the breeder.
To obtain RFID tags, you first need a Premises Identification Number from the Pennsylvania Department of Agriculture. As a pork producer, whether you own one sow or a thousand, you should have a premise ID — a number assigned by the state that enables the state to notify you if a major disease outbreak occurs. It is not available publicly and is only used for disease notification. For disease prevention, a premise ID is a must. You must have a premise ID to order RFID tags.
Official Ear Tags (Non-RFID)
For slaughter and feeder swine, an eartag or tattoo bearing the Premises Identification Number assigned by the State Animal Health Official to the premises on which the swine originated is the standard official identification method. These are distinct from RFID tags and are used primarily in commercial production and slaughter channels rather than show contexts.
Tattoos
Tattoos on the ear or inner flank of any swine qualify as official identification if the tattoos have been recorded in the book of record of a swine registry association. Official swine tattoos issued and authorized by State or Federal Animal Health Officials are also accepted on swine moving in slaughter channels. Tattoos are more permanent than tags but require more equipment and skill to apply legibly.
USDA Backtags
USDA backtags are accepted only when used on swine moving in slaughter channels. They are not a general-purpose identification method and cannot substitute for official ID in exhibition or breeding contexts.
| ID Method | Official for Interstate Movement | Required for PA Shows | Valid for Purebred Registry | Slaughter Channel Use |
|---|---|---|---|---|
| Ear Notching | Yes (if registry-recorded) | No (RFID required) | Yes (required) | No |
| 840 RFID Tag | Yes | Yes (mandatory since 2016) | Supplemental | Yes |
| Official Ear Tag (PIN) | Yes | Acceptable | No | Yes |
| Tattoo (registry-recorded) | Yes | Acceptable | Yes | Yes (with authorization) |
| USDA Backtag | Slaughter only | No | No | Yes |
One practical note: AIN (Animal Identification Number) tags look like RFID tags with an 840 number, but they cannot be read by a wand or reader — they are only visual tags and are not acceptable for Pennsylvania shows. Make sure you order the correct tag type when sourcing identification supplies. You can find a full list of approved tags on the USDA APHIS NVAP Reference Guide for Swine Identification.
State-Specific Swine Identification Rules That Affect Ear Notching in Pennsylvania
Pennsylvania’s swine identification framework operates at the intersection of state agricultural code and federal USDA-APHIS regulations. Several state-specific rules directly affect how and when ear notching fits into your compliance picture.
Health Certificates and Intrastate Movement
Any time you transport swine within Pennsylvania — with certain exceptions for animals moving between properties owned by the same person — you need a Pennsylvania health certificate (AAI-13). The health certificate must include the name and address of the consignor and consignee, the herd of origin and destination, and an accurate description of the animal including complete identification such as ear tag, tattoo, brand, registration number, ear notches, or other designations. Ear notches are explicitly recognized as a valid identifier on this certificate, provided they are legible and documented.
Exhibition Requirements
Pennsylvania has some of the more detailed exhibition requirements for swine in the mid-Atlantic region. No swine species shall be unloaded at an animal exhibition or exhibited in the Commonwealth unless each animal is accompanied by a Pennsylvania health certificate or ICVI issued by a licensed and accredited veterinarian not more than 14 days before the date of the animal exhibition. The 14-day window is strict — a certificate issued 15 days before the fair does not comply.
The Pennsylvania Department of Agriculture mandated that all show pigs must have RFID tags in their ears, and the RFID tag should start with the numbers 840. This means that even if your pig carries a perfectly notched ear with a valid registry record, you still need the 840 RFID tag to exhibit at Pennsylvania fairs and livestock shows. Ear notching and RFID are complementary, not interchangeable, in the exhibition context.
Record-Keeping for Hunting Preserves
Pennsylvania also regulates swine moved to hunting preserves. Records of all swine shall be maintained by the consignee and consignor for at least 5 years after the animal is moved to the hunting preserve and shall be made available for examination upon request by the Department. If ear notches serve as the identification method for those animals, those notch records must be part of the five-year documentation trail.
Premises Registration and Disease Traceability
Pennsylvania’s broader swine identification infrastructure is built around premises registration. If you do not have a premise ID, you can apply for one online through the Pennsylvania Department of Agriculture’s Premises Registration Form; after completing the form, you will receive your Premise ID number in a few weeks. This number underpins your ability to order official ear tags, participate in disease traceability programs, and comply with the state’s show pig RFID mandate.
The stakes for accurate identification are real. With African Swine Fever present across the world, the disease — if it were to arrive — would devastate the pork industry in the USA. Swift and correct tracking is essential to limit the spread of any disease outbreak. Ear notching, when properly recorded with a registry, contributes to that traceability chain for purebred operations.
Important Note: Pennsylvania’s swine exhibition rules have been subject to updates, including quarantine orders related to African Swine Fever biosecurity. Always verify current exhibition requirements directly with the Pennsylvania Department of Agriculture before the show season begins, as conditions and requirements can change between years.
For context on how Pennsylvania regulates other animals and livestock, see the state’s rules on backyard chicken laws in Pennsylvania and beekeeping laws in Pennsylvania, which follow a similar pattern of layered state and federal compliance requirements. If you transport animals across county lines or state borders, Pennsylvania’s pet import laws page also offers relevant context on health certificate procedures that apply broadly to livestock movement in the Commonwealth.
Ear notching remains a practical, permanent, and legally recognized identification method for registered swine in Pennsylvania — but only when it is correctly applied, accurately recorded with a purebred registry, and paired with the additional identification tools that state and federal rules require for your specific situation. Whether you are farrowing your first litter or managing a multi-breed registered operation, knowing exactly where ear notching fits in Pennsylvania’s regulatory framework protects both your animals and your business.