Ana sayfa/What is a Letter of Access (LoA)?
What is a Letter of Access (LoA)?
SHORT ANSWER
A Letter of Access (LoA) is the document that grants the right to refer to the data set held in a joint registration. A company that pays its share of the cost of generating that data may use it in its own KKDIK registration through the LoA. Without an LoA, a reference to someone else’s data is not valid in terms of data ownership.
Last regulatory review: 27 August 2026 · Reviewed by: ONAY Mühendislik technical team · Basis: KKDIK Regulation (Official Gazette 23.06.2017/30105) and its data-sharing provisions
A Letter of Access (LoA) grants a registrant the right to use existing studies and the shared data set for their registration. Under KKDIK’s joint registration principle, member registrants typically access the Lead Registrant’s data set in return for an LoA, whose price reflects the fair sharing of data costs.
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Contact ONAY Mühendislik for KKDIK and REACH support.
Official source: KKDIK Regulation — Turkish Official Gazette.
Who issues the Letter of Access?
The LoA is obtained from the party that generated the data or holds the rights to it. In practice this is usually the Lead Registrant of the joint registration, or the consortium or consultant acting on the lead’s behalf. Member registrants of the same substance approach the lead through the SIEF and request an LoA in return for their share of the data costs.
How is the LoA price determined?
There is no fixed tariff. The price depends on the data set required for the substance and on the cost-sharing rules agreed within the joint registration.
| Factor | Effect on price |
|---|---|
| Tonnage band | Higher tonnage requires a wider data set, so the share increases |
| Hazard profile of the substance | CMR or aquatic-hazardous substances need more costly studies |
| Number of co-registrants | The more participants, the lower the share per company |
| Registration type (provisional / full) | Full registration requires a more extensive data set |
| Data ownership structure | Whether the data sits with one owner or a consortium affects the price |
The LoA fee is a separate item from the registration fee paid to the Ministry and from any consultancy fee. See KKDIK registration fees 2026.
What if the Lead Registrant does not quote a price?
The most common blockage in practice is a Lead Registrant that does not respond or delays the process. This does not suspend the obligation: by 30 September 2026 every substance in scope must hold a provisional or full registration number. While waiting for the lead, the sequence is:
- Requests to the lead and any replies are kept in writing and dated; this correspondence is evidence of good faith during an inspection.
- If no offer arrives within a reasonable period, the individual provisional registration route is assessed and the reason is stated explicitly in KKS.
- If an offer arrives later, moving to the joint registration can be reassessed at the full registration stage.
- Tonnage and the substance list are confirmed by the company in writing throughout.
For the full timetable see KKDIK registration deadlines; for the joint registration structure see what a Lead Registrant is.
Obtaining an LoA, step by step
| Step | Work done | Output |
|---|---|---|
| 1. Substance confirmation | Verifying the CAS/EC number and substance sameness | Application against the correct substance |
| 2. Pre-SIEF enquiry | Checking the lead and any existing joint registration through KKS | Lead Registrant details |
| 3. Request | Approaching the lead stating tonnage and registration type | Dated written request |
| 4. Offer and cost sharing | Assessing the price and the scope it covers | LoA offer |
| 5. Payment and issue | Paying the share and the LoA being issued | LoA document |
| 6. Use in the dossier | Referring to the data in the registration dossier | Registration bound to the joint submission |
Frequently asked questions
Are an LoA and a joint registration the same thing?
No. A joint registration is several companies registering the same substance from a single data set. The LoA is the document that grants the right to refer to that data set; participation in the joint registration is evidenced by it.
Can a registration be made without an LoA?
Not where someone else’s data will be referenced — such a reference is invalid. A company may generate its own data and register individually, but that route is far heavier in cost and time.
Does an EU REACH LoA cover KKDIK?
No. An LoA issued for an EU REACH registration does not satisfy the Turkish obligation. If a non-Turkish manufacturer’s data is to be used, an Only Representative must be appointed in Türkiye and the registration submitted through KKS. See Only Representative services.
Is the LoA fee refundable?
That depends on the contract signed with the lead or the consortium. Before payment, the scope, the tonnage band and the refund conditions should be settled in writing.
Does the LoA need renewing if the tonnage band changes?
Moving to a higher tonnage band generally requires access to a wider data set and may trigger an additional payment. The lead or consortium should be informed as soon as a tonnage change is identified.
How ONAY Mühendislik supports you
We run the lead enquiry for each substance, handle the approach and correspondence with the Lead Registrant, assess the scope and tonnage suitability of the LoA offer received, and set up the individual provisional registration route where no offer is forthcoming.
Request an LoA suitability assessment · What is the KKS system? · KKDIK & REACH consultancy