How an international medical insurance claim actually works, from symptom to settlement

The route matters before the diagnosis does

The first thing an insurer establishes about a claim is not what is wrong with you. It is whether the treatment you need counts as in-patient, day-patient or out-patient, because that single classification decides which process the claim runs through, whether you have to telephone anyone before treatment starts, and whether the hospital or you will be out of pocket in the meantime.

In-patient treatment means an overnight admission. Day-patient treatment means occupying a hospital bed for a procedure without staying the night. Out-patient treatment is everything else — a consultation, a scan, a course of physiotherapy — where no bed is used. Almost every international policy makes pre-authorisation compulsory for the first two categories and optional or unnecessary for the third, and almost every policy settles the first two directly with the hospital while leaving out-patient costs to be paid by the member and reclaimed.

That is the whole shape of the process. What follows is the detail, in the order it happens, and the two places it most often breaks: a call that was never made before admission, and a deadline that expired while paperwork was being chased.

Pre-authorisation, and what it is actually for

Pre-authorisation is the insurer confirming, before treatment starts, that the proposed treatment appears eligible under your plan. William Russell's Insurance Product Information Document, dated 10 November 2025, lists it among the member's standing obligations: contact the insurer for pre-authorisation as soon as any member needs in-patient or day-patient treatment. Bupa Global, describing how it manages claims costs, names pre-authorisation of in-patient treatment alongside its direct-settlement network as one of its cost-control mechanisms.

Both of those framings are honest about what the process is for, and it is worth being clear that it serves two purposes at once.

The first is genuinely for the member. It settles the eligibility question while you still have choices. If the proposed procedure falls outside your area of cover, sits inside an inner limit that will not stretch to the full course, or is caught by a waiting period, you find out before you are lying on a ward with an unfunded bill accruing. It also triggers the guarantee of payment that lets the hospital admit you without a deposit.

The second is for the insurer. It is the point at which cost is controlled — the check on whether the procedure is medically necessary, whether the provider's charges are within what is reasonable and customary for that country, and whether a less expensive setting would do. Understanding that both purposes are in play explains why the process asks for a consent form allowing the hospital to release your medical records, and why it takes time.

The practical requirement is a notice period. William Russell's plan agreement asks for at least five days' notice of an admission, on the stated reasoning that the insurer needs that time to obtain the hospital's clinical information. Contact made inside five days may simply not complete before you are admitted.

Skipping it does not void the claim — it discounts it

The most useful thing to understand about pre-authorisation is that failing to obtain it rarely destroys a valid claim outright. It reduces it, by a stated percentage, and the percentage is in the wording.

Two things follow. The first is that a 20% or 25% reduction on a hospital admission is a large number in absolute terms, and it applies to a claim the insurer accepts as otherwise valid — you are being penalised for the process, not the treatment. The second is that the penalty is not always a percentage. Where a policy carves out an expensive territory such as the United States and covers it only on a restricted basis, the wording may make pre-authorisation an absolute condition, and treatment obtained without it is not covered at all.

Certain benefits acquire a pre-authorisation requirement partway through a course of treatment rather than at the start. Physiotherapy is the common example: the first six sessions may run on a referral letter alone, with anything beyond that requiring the insurer's agreement and, typically, a medical report. Members who assume the original referral covers the whole course discover the gap when the seventh invoice is declined.

It is also worth knowing what pre-authorisation is not. It is not an unconditional promise to pay. Wordings routinely reserve the right to unwind an authorisation if the costs turn out to relate to a condition the plan does not cover, leaving the member responsible for the bill and obliged to repay anything already settled. That is one reason pre-existing conditions should be resolved at application rather than at the point of claim.

Emergencies, where advance contact is impossible

No wording expects a member having a heart attack to telephone an insurer first. What they expect instead is contact within a short window after admission, and they set the window explicitly.

The William Russell wording provides that where you are admitted in an emergency and it was not reasonably possible to make contact in advance, the claim will be considered provided the insurer is contacted within 24 hours of admission. Miss that, and the claim faces the same exposure — possible decline, or a 20% co-insurance. The NIMBL wording allows 48 hours and, importantly, does not require the member to be the one who makes the call: the medical provider, a close relative or a relative in the first degree can do it.

That detail is the practical takeaway. The obligation is that somebody notifies the insurer, not that you do. A travelling partner or an adult child who knows your policy number and the 24-hour assistance number can discharge it while you are still in resuscitation. Where the emergency involves moving you to another country entirely, the evacuation and repatriation benefit has its own authorisation route through the assistance service, and that service — not you and not the treating hospital — usually retains the decision on whether, where and how you are moved.

The eligibility checks running behind the decision

While you are dealing with the hospital, the insurer is running a sequence of tests against the plan. Each one can reduce or refuse a claim independently of the others.

Is the treatment inside your area of cover, and is the country you are in one where your plan pays in full rather than on a restricted emergency-only basis? Is the condition acute or chronic, given that chronic conditions frequently attract day caps or a maintenance-treatment cut-off? Has the relevant waiting period expired? Is the benefit one you actually bought — on a modular plan, emergency treatment that does not result in an in-patient or day-patient admission may only be covered if the out-patient module was purchased, which surprises members who assume emergency care is universal. Is the charge within the reasonable and customary range for the country of treatment, since freedom to choose your provider is not the same as freedom to choose your provider's price?

Settlement, and who is actually out of pocket

Where the treatment is in-patient or day-patient, the default is that the insurer settles the invoice directly with the hospital, and you pay only the shortfall — the excess, any co-insurance, and anything ineligible. Where it is out-patient, the default is the reverse: you pay in full at the point of treatment and reclaim. The mechanics of both, and what to do when the arrangement fails at the hospital desk, are covered in direct billing versus reimbursement and in checking your hospital is in-network.

Cost-sharing is applied in a stated order, and the order changes the number. One wording applies co-insurance first, then the excess, then the benefit limit. AXA's published excess mechanics run the other way for limited benefits, applying the limit before deducting the excess. Neither is wrong; they simply produce different settlements on the same invoice, which is why the order is set out in the wording rather than left to practice. The interaction is explained in full under deductibles, excess and co-insurance.

Documents, deadlines and the exchange rate

A reimbursement claim needs a claim form, and above a threshold — US$500 in the William Russell wording — the treating doctor must complete and sign the clinical section of it. Take the form to the appointment. Retrieving a signature from a consultant in another country three months later is materially harder than obtaining it while you are in the room, and insurers do not pay the fee a doctor charges for completing a claim form.

It also needs fully itemised invoices and receipts, broken down by treatment, service and drug. Certain out-patient benefits additionally need a medical referral letter — physiotherapy, chiropractic and osteopathic treatment, out-patient mental health treatment, dietetic consultations, MRI and CT scans, with a specialist's referral for a PET scan. Keep the originals: wordings commonly require you to retain them for twelve months against an audit request.

Then the deadlines, which are shorter than most members assume:

On currency, the sequence is what catches people out. The amount is calculated in your policy currency, excess and co-insurance are deducted, benefit limits are applied, and only then is the balance converted into the currency you asked to be paid in. Where several invoices belong to one claim, the historic rate for the date of the final invoice is typically used for all of them; where a course of treatment straddles a renewal, each policy year is settled at its own rate. Insurers state plainly that they do not carry the currency risk between treatment and payment, and on a large claim in a volatile currency that is a real exposure rather than a technicality.

What to sort out before any of this applies

Find the pre-authorisation list in your own table of benefits and read it once, in advance. Put the 24-hour assistance number and your policy number somewhere a family member can reach them, because the emergency notification window does not care who makes the call. Check which of your local providers bill your insurer directly. And if a claim comes back reduced or refused, the reasoning and the escalation route are set out in declined claims and how to appeal — a proportion of decisions turn on evidence that was available all along but never submitted. For low-level concerns that do not need a claim at all, the virtual GP and second opinion services already included in most plans sit entirely outside this process.