Going live with Tesco, Sainsbury's and Lidl: an EDI checklist

In short: going live with a UK grocer is a four- to eight-week project with three phases: connectivity, message testing and a parallel run. The retailer sets the pace, so the fastest way through is to have your answers ready before their EDI team asks. This guide lists what to do, what to ask and what to test for each of Tesco, Sainsbury’s and Lidl, plus the mistakes that most often add weeks.

The shape of every go-live

Whatever the retailer, the steps are the same:

Phase	What happens	Typical duration
1. Commercial set-up	Buyer lists your products; supplier account, GLN/ANA, depots and product codes are created	1–3 weeks (mostly waiting)
2. Connectivity	AS2 certificates exchanged or SFTP credentials issued; a test file passes both ways	2–5 working days
3. Message testing	Retailer sends test orders; you return test ASNs and invoices; they are checked against the specification	1–3 weeks
4. Parallel run	Real orders flow by EDI alongside the existing method (email, portal, fax)	1–2 weeks
5. Live	EDI is the single source of truth; the old channel is switched off

Phase 1 is out of your hands. Phases 2 to 4 are where preparation pays off.

Before you talk to any retailer

Have these to hand. Every EDI team will ask for them, and a delay answering is a delay to the project.

• Your GLN (Global Location Number) from GS1 UK, plus GLNs for each despatch location if you ship from more than one site.
• Your GS1 company prefix and confirmation that you can allocate SSCCs from it.
• GTINs for every consumer unit and outer case, matched to the retailer’s product codes.
• Your VAT number and the legal entity name that will appear on invoices.
• A named EDI contact (you or your provider) who can answer technical questions the same day.
• Which documents you will exchange: orders in, order response, ASN, invoice, and whether you need remittance advice and forecasts.
• Your warehouse process: who picks, what system confirms the pick, and how the pallet label is printed. The ASN timing depends on this.

Tesco

What Tesco will send you

The Tesco Supplier EDI guide and message specifications for your category, an EDI onboarding form, and details of the Tesco test environment. Tesco onboards through a small number of approved connectivity routes; check which one your provider supports.

Questions to ask Tesco

1. Which standard and version for our category: Tradacoms or EDIFACT D96A?
2. Which depots will order from us, and what are their GLNs and delivery windows?
3. Are we in scope for order responses (ACKHDR / ORDRSP) or only orders, ASNs and invoices?
4. Which Tesco product identifier goes on the ASN and label: TPNB or TPNA?
5. Is self-billing in scope, and if so which invoice messages are switched off?

Test scenarios Tesco will run

• Standard order → ASN → invoice, single depot, homogeneous pallets.
• Order with a short-shipped line; ASN and invoice must both reflect the reduced quantity.
• Order with a cancelled line (quantity zero on the ASN).
• Mixed pallet ASN with multiple GTINs under one SSCC.
• Invoice with multiple VAT rates if your range includes both zero-rated and standard-rated lines.
• Duplicate document number, which Tesco must reject.

Tesco pitfalls

• Sending the ASN per purchase order when the delivery consolidates several orders. Tesco wants one ASN per delivery.
• Invoice totals rounding differently from Tesco’s calculation. Tesco calculates line VAT and rounds per line; match their method.
• Pallet label barcode grade. Tesco audits labels at depot and scores suppliers; a grade below B will show up in your compliance report even if the pallet was received.

Timeline

Expect six to eight weeks from onboarding form to live, of which two to three are testing. Tesco’s EDI team works to a queue; respond to their test feedback within a day to keep your slot.

Sainsbury’s

What Sainsbury’s will send you

A supplier EDI pack covering EDIFACT (and Tradacoms where still supported), the connectivity form, and access to their supplier portal where test results and compliance are reported.

Questions to ask Sainsbury’s

1. EDIFACT or Tradacoms for our supplier account, and which EDIFACT version and subset?
2. Do they want AI 15 (best before) or AI 17 (use by) on our pallet labels, per product?
3. Which depots and which delivery booking system (and does the booking reference go on the ASN)?
4. Are we required to send order responses, and within what time?
5. Invoice matching tolerance: what price and quantity variance triggers a query?

Test scenarios Sainsbury’s will run

• Order → ASN → invoice for an ambient line and a chilled line, to exercise date and batch fields.
• ASN where the BBE on the label, the ASN and the case must match; this is checked physically at depot during parallel run.
• An over-delivery attempt, which the ASN validation must reject before sending.
• Order response with a substitution or partial acceptance, if in scope.
• Credit note against a previously invoiced delivery.

Sainsbury’s pitfalls

• Best-before mismatches between label and ASN. Sainsbury’s uses the label to drive rotation at depot; this is treated as a labelling failure, not a data error.
• Mixed pallets without the “MIXED” indicator in the label text zone.
• Sending invoices before the ASN has been received. Sainsbury’s matches invoice to ASN, so an early invoice sits unmatched.

Timeline

Four to six weeks, typically. Sainsbury’s testing is more automated than Tesco’s and turnaround on feedback is fast, so the critical path is usually your own warehouse readiness.

Lidl

What Lidl will send you

Lidl GB’s EDI guidelines (EDIFACT throughout), an AS2 connection form requesting your certificate and URL, and a test plan. Lidl is the most prescriptive of the three on timing.

Questions to ask Lidl

1. AS2 endpoint details, certificate requirements (key length, expiry) and whether they require synchronous or asynchronous MDNs.
2. The EDIFACT version and subset for ORDERS, DESADV and INVOIC, and whether CONTRL is mandatory in both directions.
3. The ASN timing rule: is it 30 minutes from despatch, and how do they measure despatch?
4. Which Lidl item numbers and delivery note references must appear on the pallet label free-text zone.
5. How consolidated deliveries to a regional distribution centre should be represented: one DESADV per delivery note or per vehicle?

Test scenarios Lidl will run

• AS2 connectivity test with MDN returned both ways, including a deliberately failed signature to confirm you handle rejection.
• ORDERS received and CONTRL returned within the agreed window.
• DESADV with one SSCC per pallet, correct CPS hierarchy, and the delivery note number in BGM.
• DESADV timing test: order at a stated time, despatch confirmed, ASN must arrive within 30 minutes.
• INVOIC with Lidl’s required references (delivery note number, order number, and their supplier number) and correct tax summary.

Lidl pitfalls

• AS2 certificate expiry. Lidl will not remind you; a lapsed certificate stops all traffic. Diary the renewal with a month’s margin.
• Duplicate SSCC within a delivery. Lidl rejects the whole DESADV, not just the pallet.
• Late ASNs caused by a manual “send” step or a batch job that runs every hour. Trigger the ASN from the pick confirmation.
• Sending an ASN for a delivery that then gets split across two vehicles. Lidl needs one ASN per physical delivery.

Timeline

Lidl’s process is efficient and mostly technical: three to five weeks if your AS2 and DESADV are ready, with the timing test usually being the one that needs a second attempt.

The parallel run

Whichever retailer, use the parallel run properly. For every real order during the run:

1. Confirm the EDI order matches the order received through the old channel, line by line.
2. Send the ASN by EDI and keep the paper delivery note on the vehicle.
3. Check the retailer’s receipt against the ASN the next day; chase any variance.
4. Send the invoice by EDI and confirm it matched (via portal or remittance) before switching off the old invoice route.

Do not switch off the old channel until you have had at least one full week with zero variances. A parallel run that ends early because “it looks fine” is the source of most first-month disputes.

Pitfalls common to all three

• Warehouse not ready. EDI can be live in days; a warehouse that has never scanned a pick or printed an SSCC label cannot. Start the warehouse work in phase 1, not phase 3.
• Master data gaps. A GTIN missing from the retailer’s system, or a product code mismatch, will fail every ASN for that line. Reconcile your product list against the retailer’s before testing.
• Nobody watching acknowledgements. A rejected message that nobody sees is a missed delivery. Make sure rejections raise an alert to a person, not just a log entry.
• Single point of failure. If one person knows how the EDI works and is on holiday when Tesco changes their spec, you have a problem. Document it or use a provider who does.
• Retailer spec changes. All three change specifications periodically. Ask to be put on the retailer’s EDI bulletin list and check for updates quarterly.

A week-by-week plan

Week	Activity
1	Commercial forms in; GLNs, GTINs, VAT confirmed; retailer specs requested; warehouse process mapped
2	Connectivity (AS2 or SFTP) tested; product master data reconciled with retailer
3–4	Message testing: orders in, ASNs and invoices out; label samples verified
5–6	Parallel run on live orders; variances chased daily
7	Old channel switched off; first month’s compliance report reviewed

How FTP EDI helps

We have taken suppliers live with Tesco, Sainsbury’s and Lidl many times, and every retailer’s specification, test plan and timing rule is already built into the platform. We handle connectivity (AS2 certificates, SFTP), run the test cycle with the retailer’s EDI team on your behalf, generate compliant ASNs and labels from your warehouse’s pick data, and chase every acknowledgement so nothing fails silently. Most suppliers are live within three weeks of the retailer issuing credentials.

• See how onboarding works on the product tour and read how it works.
• Retailer specifics: Tesco, Sainsbury’s, Lidl.
• Related solutions: ASNs and GS1-128 labels, warehouse integration, invoicing.