Sheep identification in Australia is governed by the National Livestock Identification System (NLIS) — the world's most comprehensive mandatory livestock traceability system, linking individual animals to properties through a central database from birth to slaughter. For sheep and goats, NLIS identification is mandatory for all animals leaving their property of birth, and producers who move untagged sheep face significant legal and commercial penalties. Understanding the NLIS system, the tag types and colours used in your state, and the correct application technique is a fundamental requirement for every Australian sheep producer, from large-scale commercial operations to small lifestyle properties with a handful of animals.

How the NLIS system works for sheep

NLIS for sheep and goats uses two identification methods: visually readable plastic ear tags and, in some states and for certain classes of stock, electronic RFID tags. Unlike the cattle NLIS system — which uses individual electronic tags that track each animal through its entire life — the sheep and goat NLIS system is primarily a mob-based traceability system. Tags identify the property of birth (through a unique Property Identification Code, or PIC, stamped or printed on the tag), and the NLIS database records mob-level movements between properties.

The central component of the system is the Property Identification Code (PIC) — an 8-character alphanumeric code that uniquely identifies every livestock property in Australia. Your PIC is assigned by your state department of agriculture when you register as a livestock producer. It is the critical link between your animals and your property in the national database. If you do not have a PIC for your property and you keep livestock that will move off that property, register through your state agriculture department immediately — operating without a registered PIC is illegal for livestock producers.

NLIS tag types for sheep and goats

Visual ear tags: plastic tags stamped or printed with the producer's PIC and, in most states, a unique animal number within the tag series. Visual tags allow handlers to read the identification without electronic equipment and are the minimum requirement for most sheep movements in Australia. Tags must be approved by the NLIS scheme — not all commercially available ear tags are approved. Purchase only from suppliers who explicitly state their tags are NLIS-approved for your state.

Electronic NLIS tags (RFID): contain a radio frequency identification chip that stores the animal's unique NLIS number, readable with a handheld or raceway reader in less than a second. Electronic tagging of sheep is mandatory in Victoria for all sheep and goats moving off their property of birth, and is becoming mandatory or strongly incentivised in other states. Some saleyards and processors now require or prefer electronic tags because they allow fully automated scanning of animals through races, eliminating manual reading errors. Check your state's current requirements — the shift to mandatory electronic identification for sheep is progressing across Australia.

Breeder tags vs transaction tags: some states use a two-tag system. A breeder tag is applied at birth and stays with the animal for its entire life — it identifies the property of birth. A transaction tag may be required or optional for subsequent movements. Check your state's specific tag requirements, as they vary.

The NLIS colour coding system

NLIS ear tags for sheep and goats use a nationally standardised colour coding system that indicates the year of birth of the animal. The colour rotates on a 12-year cycle, allowing handlers to estimate an animal's age visually by tag colour without needing to read the tag or examine dentition. The standard colours and their assigned years:

  • Orange: 2015, 2027
  • Aqua/Teal: 2016, 2028
  • White: 2017, 2029
  • Lime green: 2018, 2030
  • Lilac/Purple: 2019, 2031
  • Yellow: 2020, 2032
  • Red: 2021, 2033
  • Sky blue: 2022, 2034
  • Pink: 2023, 2035
  • Tan/Fawn: 2024, 2036
  • Green: 2025, 2037
  • Black: 2026, 2038

For 2026, the correct NLIS tag colour for lambs born this year is black. This is the tag colour you must apply to all lambs born in 2026 that will move off your property. Using the wrong year-colour tag is a compliance issue — it disrupts traceability by indicating an incorrect birth year to subsequent handlers and processors.

Note that this colour system is for NLIS tags specifically — additional management tags (pain relief tags, health event tags, or producer-applied management markers) may be any colour and are supplementary to, not a replacement for, the mandatory NLIS tag.

When tags must be applied

Requirements for the timing of tag application vary slightly between states, but the general national standard is: sheep and goats must be individually tagged before leaving their property of birth. In practice, this means tagging at marking (lamb marking, which typically occurs when lambs are 4 to 8 weeks old) is the standard practice, giving animals their tags well before the first possible movement off the property.

Some state regulations require tagging before a specific age regardless of planned movement — check your state agriculture department's current livestock identification requirements for the precise age-based obligations. Victoria, NSW, Queensland, South Australia, and Western Australia each have specific regulations that are updated periodically.

National Vendor Declarations and movement recording

NLIS identification is only part of the traceability obligation. Every time sheep are moved between properties — for sale, agistment, slaughter, or any other purpose — the movement must be recorded through a National Vendor Declaration (NVD). The NVD is a statutory declaration that records the vendor's PIC, the buyer's or destination PIC, the number and class of animals, health declarations, and treatment records relevant to food safety.

NVDs are available through your state Livestock Biosecurity organisation or equivalent, through saleyards, and through many produce stores. Online NVD systems (eMVD — electronic Mob Vendor Declaration) are available through state NLIS portals and are increasingly the preferred method. Failure to complete a vendor declaration when moving sheep is an offence — and in the event of a disease investigation, an inability to trace your animals through the supply chain because of missing NVDs creates serious legal and commercial exposure.

How to apply NLIS tags correctly

Tag placement and application technique affect both animal welfare and tag retention. A poorly placed or incorrectly applied tag will tear out more readily, create unnecessary tissue damage, and may cause ear infections that require treatment. The correct technique:

  • Location: apply the tag to the middle third of the ear — not close to the head (where major blood vessels run) and not near the tip (where the ear is thinner and tags are more prone to tearing). The middle third offers the best combination of vascular distance and tissue thickness for long-term retention.
  • Avoid the main vessels: hold the ear up to light before tagging — the major blood vessels are visible as darker lines. Place the tag between vessels rather than through them. Tagging through a major vessel causes significant bleeding and increases the risk of post-tagging infection.
  • Use clean, sharp, approved applicators: use only the applicator specifically designed for the tag brand you are applying. Tag-specific applicators ensure the pin passes cleanly through the ear and the locking mechanism engages correctly. A blunt or wrong-sized applicator tears tissue unnecessarily.
  • Wipe the applicator with antiseptic between animals during tagging if moving through a large mob — the applicator pin can transfer infection between animals. Methylated spirits on a cloth between each application is standard practice in professional marking operations.
  • Check retention after application: pull the tag gently to confirm the locking mechanism is fully engaged. A tag that releases easily has not been applied correctly — reapply in a slightly different location if the pin hole has been torn.

Record keeping

Maintain a property livestock register recording all tags applied — the tag series, PICs, year colour, and dates applied. This is a legal requirement under most state livestock identification regulations and is your primary defence in the event of a compliance inspection or disease investigation. A simple spreadsheet or notebook recording tag numbers issued, dates of application, and the mob they were applied to is adequate for most small operations.

For more on sheep management, see our Sheep Guides and Sheep FAQ.

For more, see our Australian Sheep Breeds: Complete Guide to the Most Important Breeds for Australian Conditions and The Drenching Guide: Worming Cattle, Sheep & Goats in Australia.