When a higher-priced backup supplier protects overseas orders

The decision starts with a specific component and a fixed group of orders. Operations defines the cover it needs, finance sets an affordable cash limit, and procurement compares routes against that objective. This gives a purchasing team a way to choose between extra stock and approved backup suppliers without paying for supply that arrives too late to help.

Establish which supply can cover the orders

Fix the component revision, order quantities and dates when production needs each component, allowing time afterwards for assembly, inspection and delivery overseas. Choose a disruption to test, such as an outage at the regular supplier's factory, and agree how many component requirements must be met on their original dates. Lock that objective and the cash ceiling before ranking quotes.

Run a daily stock balance. Start with usable stock, add receipts available before that day's production, and subtract the components required that day. A receipt available after consumption starts covering the following day. Record shortages and check storage and handling limits throughout. The lowest quote has no place in the feasible set if its components are unapproved, too late or unavailable in the quantities needed.

Check whether the backup shares the failure being tested. A separate trading name can still depend on the same factory, upstream input or transport route. The Government Office for Science's supply-chain foresight report, updated in September 2026, describes how shared dependencies can transmit disruption. For a factory-outage test, require evidence that the backup can supply independently of that factory. A port-closure test would require a separate route check.

Keep extra stock in the comparison. The Department for Business and Trade's resilience framework includes diversification, stock and surge capacity among the available responses. Brian Tomlin's published sourcing model distinguishes inventory, regular reliable sourcing and contingent capacity. Its capacity assumptions underline a practical question for a backup quote: how much approved supply can be made usable when called upon?

Separate additional cost from earlier cash

Use the same orders, cost horizon, currency and tax basis for every route. Include changed component costs, freight, approval work, storage, financing and reservation fees. Account for remaining stock at the horizon consistently. The Association of Chartered Certified Accountants' relevant-cost guidance bases decisions on future cash flows changed by the choice. New fixed costs belong in the comparison; unchanged common costs and money already spent do not.

If the same components will eventually be bought whichever route is chosen, their normal purchase cost is common. Buying them earlier can still require extra cash now and create financing costs. If volumes, cancellations or residual stock differ, finance must calculate those differences before using this comparison.

Keep two separate totals. Additional cost is the route's relevant future cost minus the baseline's for the agreed order cohort. Peak additional cash is the largest cumulative outflow difference from the baseline payment calendar. Include purchases brought forward in that cash total. Eliminate routes that breach the agreed ceiling, then choose the unique lowest additional cost among all routes that meet the delivery objective.

This is a proposed purchasing comparison for a protection objective the business has already chosen. It does not estimate disruption probability or establish whether that objective is worth buying.

A higher quote that costs less overall

This hypothetical manufacturer must build 40 pumps over 20 working days, using one approved component per pump, two per day. Component-needed dates already allow downstream assembly and overseas delivery time. It has 12 usable components. During the specified factory outage, the regular supplier delivers nothing until day 16, then two usable components before production each day through day 20. Existing supply covers 22 requirements, leaving 18 uncovered on time.

Operations requires all 40 requirements met on their dates. Finance sets a £1,600 peak additional-cash ceiling. All 40 orders will ultimately be manufactured even without protection, although 18 would be late. The 18 eventual regular purchases at £30 each therefore cost £540 under every route. Other costs are identical, recoverable tax is excluded, and no stock remains after the cohort is completed.

The site stores at most 20 components. Three evidenced arrangements can cover the gap:

Both backups are fully approved and independent of the failed factory. Their confirmed quantities and dates cover the gap. All option payments occur before the corresponding normal purchase payments would fall due; no other cash-flow differences arise. The table's cash figures are therefore the peak differences from that baseline calendar.

All three routes satisfy the same cover and cash limits. B has the highest component price and the lowest additional cost. Its smaller fee saves £64 against C, while it costs £288 less than storing the buffer. Comparing C and A first, or reversing the table, still leaves B as the unique minimum of the full qualifying set.

B's timing is decisive. Move its usable receipt to after day 8 and it leaves days 7 and 8 short, so it fails. C then wins at £736 while the buffer remains feasible. With 40 suitable components already available, the baseline could meet the objective at zero additional cost and avoid buying any extra cover.

Complete one allocation sheet before committing

For one live component, retain the following record with the quotes. This applies the same comparison to your own orders.

The completed example reads: B qualifies; additional cost £672; peak cash £1,212 against £1,600; procurement confirms its quote, operations verifies usable arrival before day 7, and finance checks payments before commitment.

Use these routes to finish the sheet:

• Evidence check. A missing decision-critical input stops allocation. Procurement obtains it, engineering/quality confirms approval and finance confirms money. Re-run before quote expiry or commitment, whichever comes first. A proven infeasible route can be excluded without researching costs that cannot change its exclusion.
• No feasible cover. Operations revises the objective, delivery plan or route with finance and customer-facing staff before the earliest dependent date or commitment. Stop purchase approval against the unmet objective until the revised plan is checked.
• Retain baseline. If it is the unique lowest-cost qualifying route, operations retains it and checks the dated plan before the first component requirement.
• Select route. Procurement confirms the unique cheapest qualifying route; operations verifies arrival before its first dependent requirement and finance checks cash before commitment.
• Exact tie. Finance reconciles cost scope and dates before commitment. If equality remains, operations records a separate choice between equivalent routes. The comparison stops without ranking them.

For a selected route or retained baseline, changed stock, approval, receipts, dependencies, cash terms or expired quotes reopen the comparison before commitment. Put one current quote through this sheet with operations, procurement and finance before its next purchase allocation.