FSMA 204 Traceability Lot Codes (TLCs): A Complete Guide
Traceability Lot Codes are the connective tissue of FSMA 204. Every Critical Tracking Event requires one. Here's how to get them right.
What Is a Traceability Lot Code?
A Traceability Lot Code (TLC) is a descriptor (often a number, code, or combination) used to identify a traceability lot. Under 21 CFR 1.1310, every food on the Food Traceability List must carry a TLC that connects it to the Critical Tracking Events (CTEs) in its supply chain.
Think of a TLC as a lot's passport. It travels with the food from farm to fork. When the FDA needs to trace a contaminated product, the TLC is how they follow the trail.
TLC Requirements by Critical Tracking Event
Assign a TLC at harvest. The TLC must uniquely identify the lot, typically a combination of farm, field, date, and commodity.
Maintain the TLC assigned at harvest. If lots are not commingled, the TLC carries through.
If you create new consumer-facing lots, assign a new TLC. Record the link between the original harvest TLC and the new pack TLC.
Include the TLC on shipping documents (BOL, ASN). The receiver must be able to trace back to your TLC.
Record the TLC from the shipper. If you assign your own internal lot code, maintain the mapping to the original TLC.
When inputs are combined into a new product, assign a new TLC. Record all input TLCs that went into the output.
The Transformation Challenge
Transformation CTEs are where TLC tracking gets complex. When you combine romaine from three different harvest lots into a single salad kit, you must:
- Assign a new TLC to the output product
- Record all input TLCs that went into it
- Maintain this mapping for at least 2 years
This input-to-output TLC mapping is what the FDA uses to trace contamination backwards through your supply chain. Missing or incomplete mappings are the #1 compliance gap we see in food manufacturing operations.
TLC Best Practices
Use a consistent format
Standardize your TLC format across facilities. A common pattern: FACILITY-DATE-SEQ (e.g., SAL-20260301-001).
Include the date
Embedding the production or harvest date in the TLC makes sorting and filtering much faster during a recall.
Avoid reuse
Never reuse a TLC, even across years. If you harvest romaine on March 1 every year, each year's lot must have a distinct code.
Make it scannable
Encode your TLC in a barcode (GS1-128 or DataMatrix) so it can be captured at receiving without manual entry.
Document your scheme
Write down your TLC assignment logic. The FDA may ask how you generate codes during an inspection.
Validate Your TLCs
Use the free TLC Format Check. FDA does not set one TLC format.