Supplier lead time: planned vs actual and quote checks
Catch a stale ERP lead time before it releases orders late, and release long-lead items before the rest of the BOM.
A planned lead time that no longer matches reality releases every order built on it too late. Checking the lead time your ERP uses against what actually happened, and pulling long-lead items out of the bill of materials so they release first, keeps your schedule built on numbers your planner can trust.
What is supplier lead time?
Supplier lead time is the time between placing a purchase order and having the part in your stockroom, ready to issue. It is not just the supplier's shop time. Your order takes time to reach them, the part takes time to travel back, and receiving has to inspect and post it before your planning system counts it as available.
The number that matters for scheduling is whatever value your ERP uses to work backward from a need date to a release date. If that number is wrong, every order built on it releases at the wrong time, and nobody notices until the part doesn't show up.
What goes into a quoted lead time?
A supplier's quoted lead time often only covers what happens once the material to make your part is already on the shop floor. It commonly leaves out the raw material's own delivery time, any outside processing such as heat treat or plating, and the first article the part still has to pass. Ask what the number assumes.
What a quoted lead time may leave out
A stacked timeline showing an illustrative example of a supplier's quoted 8-week lead time next to the fuller set of stages a part actually needs: order processing, raw material procurement, outside processing, manufacturing, first article, transit, and receiving and inspection. The quoted 8 weeks covers mainly the manufacturing stage, and sometimes transit depending on the quote's terms; raw material procurement, outside processing and first article add more weeks the quote may not mention, so the real time from PO to usable stock can run well past what was quoted.
- 1
Order processing
- Illustrative duration
- 3 days
- Counted in the supplier's quoted 8 weeks?
- No, happens before the supplier's clock starts
- Who is responsible for this stage
- Your buyer and the supplier's order desk
- 2
Raw material procurement
- Illustrative duration
- 5 weeks
- Counted in the supplier's quoted 8 weeks?
- No, the quote assumes material is already on hand
- Who is responsible for this stage
- Supplier's purchasing
- 3
Outside processing (for example heat treat or plating)
- Illustrative duration
- 2 weeks
- Counted in the supplier's quoted 8 weeks?
- Sometimes, depends whether the quote covers the outside processor's queue
- Who is responsible for this stage
- Supplier, via its outside processor
- 4
Manufacturing
- Illustrative duration
- 7 weeks
- Counted in the supplier's quoted 8 weeks?
- Yes, this is usually what the quoted 8 weeks means
- Who is responsible for this stage
- Supplier's shop floor
- 5
First article
- Illustrative duration
- 1 week
- Counted in the supplier's quoted 8 weeks?
- No, a new part or a changed part still needs first article after the quoted weeks
- Who is responsible for this stage
- Supplier and your quality team
- 6
Transit
- Illustrative duration
- 4 days
- Counted in the supplier's quoted 8 weeks?
- Sometimes, check whether the quote is dock-to-dock or ship date only
- Who is responsible for this stage
- Carrier
- 7
Receiving and inspection
- Illustrative duration
- 2 days
- Counted in the supplier's quoted 8 weeks?
- No, this happens on your side, after the supplier's quote ends
- Who is responsible for this stage
- Your receiving and quality team
A supplier's quoted number often covers only its own shop time, not raw material, outside processing or first article.
Ask the supplier directly whether the quoted weeks start when you place the order or once the material is already in-house, whether they cover the outside processor's own queue or only the supplier's operations, and whether the part has already cleared first article or that step is still ahead of you. A quote that only answers the machining question can run weeks short of the number you actually need.
Is a quoted lead time a contractual promise?
A quoted lead time is not a promise on its own. It's what the supplier expects when nothing goes wrong. The binding date is the one the supplier accepted on your purchase order, or the lead time term in a long-term agreement. Check which one you are holding.
A sales quote moves as fast as the supplier's backlog does, and a supplier chasing your business will sometimes quote the number that wins the order, even when the shop can't hold to it. Once the order is placed, confirm the ship date the same way you would confirm any other line, and hold the supplier to the confirmed date on the PO or the agreement, not the number from an earlier email. See purchase order acknowledgement for turning that quote into a confirmed date.
In the United States
A DPAS rating does not shorten your supplier's process time. Under 15 CFR 700.14(a), the supplier must schedule its operations, including buying the production items it needs, in time to meet the rated order's delivery date. If the supplier can't buy the material in time, it must fill the rated order from its own inventory. 15 CFR 700.14(d). A DO rating gives your order production preference over unrated work only if that is what it takes to meet the date, and a DX rating outranks both DO and unrated work. 15 CFR 700.14(a)-(b). Neither adds a shift to the supplier's floor or shortens the weeks a casting or a forging takes to make. If the honest lead time still misses your need date, work the gap the same way you would on an unrated order, and see DPAS-rated orders for requesting special priorities assistance. The DPAS rests on Title I of the Defense Production Act, which expires on December 11, 2026 unless Congress extends it. 50 U.S.C. 4564(a).
Which lead time does MRP use?
MRP does not go looking for the supplier's latest number. It uses whatever procurement lead time is stored against that part (and sometimes that supplier) in your ERP, and if nobody has updated that field, MRP keeps scheduling against a number that stopped being true months ago.
SAP, for example, splits the number into three parts: a purchasing processing time set once for the plant, and a planned delivery time and goods receipt processing time on each material's MRP 2 view. SAP can take the planned delivery time from the info record or scheduling agreement that MRP picks as the source, but only if your MRP group is set up to do that; otherwise MRP uses the planned delivery time on the material master. Ask whoever owns your MRP settings which value your plant reads, and keep that one current. A number the supplier gave your buyer by email, but that never made it into that record, changes nothing about when MRP releases the next order. If the stored lead time puts an order's release date in the past, MRP flags it with an exception message; a lead time that is merely too short raises none. MRP exception messages.
How often should you check planned lead times against actual?
Every quarter, pull the last several receipts for each part number against the lead time sitting in your ERP. MRP keeps releasing orders on the old schedule right up until one arrives late, and by then it is too late to have released that order earlier.
Planned vs actual lead time check
A worked example table with four illustrative part numbers, comparing each part's planned lead time stored in the ERP against the average and the 90th-percentile actual lead time measured from its last several purchase orders, showing the gap and a recommended action for each. Two parts show the planned lead time still roughly matching actual performance and need no change, one part shows the actual lead time has quietly grown well past the planned value and needs the ERP field updated, and one part shows a wide spread between average and 90th-percentile actual lead time and needs to be planned against the slower figure because it gates a kit.
| Part (illustrative) | Planned lead time in ERP | Average actual lead time (last 8 receipts) | 90th-percentile actual lead time (illustrative) | Gap vs. planned | Recommended action |
|---|---|---|---|---|---|
| A-1042, bracket, machined | 4 weeks | 4.1 weeks | 4.6 weeks | Minimal | No change; keep on the quarterly review cycle |
| B-2210, fastener, standard | 2 weeks | 1.6 weeks | 2.2 weeks | Minimal, runs early | No change; low value, not worth tightening further |
| C-3087, forging, gates final assembly | 10 weeks | 12.8 weeks | 15.5 weeks | Planned lead time is 5+ weeks short of the slow case | Update the ERP lead time field and review with the supplier; treat as a long-lead item |
| D-4400, custom casting, sole source | 9 weeks | 9.4 weeks | 13 weeks | Average looks fine; 90th percentile does not | Plan releases against the 90th-percentile figure, since this part has no schedule slack |
A part's planned lead time can look fine on average and still be wrong for the number that actually matters: the slow delivery that gates the kit.
Spend the review on the parts that gate a kit. A commodity fastener that runs two days early every time doesn't need your attention; a casting that has quietly grown from 10 weeks to 14 does, because the next order you release against the old number arrives late.
How do you measure actual lead time?
Pull the PO create date and the date the receipt posted to stock for several past orders, and look at the spread, not the average. For example, a supplier who delivered in 8, 9 and 19 weeks doesn't have a 12-week lead time; they have a lead time that's usually fine and occasionally leaves your kit short.
The average erases the delivery that hurts you. Sort the actual lead times you pulled and plan against one of the slowest deliveries on that list for any part that has no room to slip. For a part with slack in the schedule, the average may be good enough.
How do you find and protect long-lead items?
A long-lead item is a part whose lead time is long enough that you have to order it before the rest of the bill of materials, often before the design is final, or the whole build waits for it. Sort the bill of materials by lead time, and release the longest items first.
The parts at the top of that sort are your long-lead items: forgings, castings, custom-wound components, anything with its own queue at a specialty supplier. Release a purchase order for those parts as soon as the design is stable enough to trust, even while the rest of the bill of materials is still being finalized. When the drawing isn't fully released yet but the part's lead time won't wait, at-risk authorization lets the supplier start on your authority instead of a completed drawing.
A part can become long-lead quickly. When a supplier's own material goes on allocation, for example, a part that shipped in 10 weeks last quarter can quote 30 this quarter, because your order is now competing with everyone else's for the same casting slot or the same wafer run.
When a supplier's new date means an open order will arrive after the part runs short, a readiness signal opens a task, and Cartograph hands it to your team or Scout Agent. Scout emails and calls the supplier for a firmer date, within the permissions your team sets.
Questions teams ask
Does a short lead time in the ERP always mean a short wait?
No. If nobody has checked that field against real receipts, a short number in the system just means the drift hasn't been caught yet. Check it against the last several receipts before you plan on it.
Who owns the lead time field?
Whoever owns your MRP or planning settings, usually the planner or the buyer for that part. Check it against actual receipts each quarter rather than waiting on a supplier's email.
What's the difference between a long-lead item and a critical part?
A long-lead item is defined by time: you have to order it before the rest of the bill of materials, or the build waits for it. A part can be critical for other reasons, such as being single-sourced or safety-related, even with an ordinary lead time. Some parts are both, and those deserve the closest watch.
Does expediting fix a long-lead item that's already running late?
Sometimes. Expediting works on an order already placed whose date now misses the need date; see expediting for the recovery options.
If your team spends hours each day finding orders that will now land after the part runs short, talk to our team about how Cartograph's readiness signals open those expedite tasks.
This article is general information, not legal or tax advice. Check how the rules apply to your business with your legal or tax advisor.
Sources (2)
- 15 CFR 700.14, Preferential scheduling, paragraphs (a) and (b)
- SAP Help Portal, S/4HANA: Scheduling for External Procurement (purchasing processing time + planned delivery time + goods receipt processing time; info record or scheduling agreement used as the MRP source only when the material's MRP group is configured for it, otherwise the material master's planned delivery time applies)