You've been told you need a major operation. Or a cancer diagnosis has just landed. Or your child has been given a rare neurological label, and the consultant has spent eight minutes explaining it. The question that hits almost everyone next is the same: am I sure this is the right call?
In Spain you have a legal right to a second medical opinion — a segunda opinión médica — and if you hold a private health policy with Sanitas or Caser, that right extends to an international expert review from the world's leading specialists, at no extra cost. Most expats never use it because they don't know it exists. This guide explains exactly how the system works, when to invoke it, and how to navigate the paperwork.
What's in this guide
- Your legal right to a second opinion in Spain
- Regional differences — Andalucía, Madrid, Valencia, Cataluña
- When a second opinion makes real sense
- Getting a second opinion in the public system
- Sanitas Segunda Opinión — how it works
- Caser Segunda Opinión Médica — how it works
- Best Doctors, MD Anderson and the international network
- The documentation you'll need
- Timelines — how long the process takes
- Common pitfalls expats run into
- Choosing a policy with strong second-opinion cover
- FAQs
1. Your legal right to a second opinion in Spain
The foundation is Ley 41/2002, de 14 de noviembre, básica reguladora de la autonomía del paciente — the Patient Autonomy Act. It doesn't spell out a free-standing "right to a second opinion" in the way some patients expect, but it does guarantee two things that together make second opinions possible:
- The right to information — Article 4 establishes that every patient is entitled to truthful, complete information about their diagnosis, prognosis and treatment options, in a way they can understand.
- The right to a copy of their medical history — Article 18 gives you the right to obtain copies of your historia clínica, including test results, imaging and consultant reports. Without this, a second opinion is impossible.
You can read the full text on the official state gazette at BOE — Ley 41/2002. It's the bedrock of patient rights in Spain and applies in both the public system (SNS) and to private providers.
On top of that national framework, every autonomous community has passed its own patient-rights law that fleshes out the detail — and crucially, several of them explicitly recognise the right to a second medical opinion in defined circumstances. That's where regional differences come in.
2. Regional differences — Andalucía, Madrid, Valencia, Cataluña
The Spanish healthcare system is decentralised. Each of the 17 autonomous communities runs its own public health service and writes its own patient-rights legislation. Four of the most expat-heavy regions handle the second opinion right quite differently.
Andalucía
The clearest framework. Andalucía's Decreto 127/2003 explicitly created a right to a second medical opinion within the Servicio Andaluz de Salud (SAS) in specified situations: confirmed malignant tumours, rare diseases, neurosurgical procedures, organ transplant decisions and treatments with high risk of mortality. You apply to your regional health authority; the SAS designates a different specialist (usually at a different hospital) to review the case. The opinion is binding only insofar as you can then choose which path to follow.
Madrid
The Comunidad de Madrid recognises the right under Ley 12/2001 de Ordenación Sanitaria and subsequent patient-rights instruments. It applies broadly to oncology diagnoses, complex surgery proposals and serious paediatric cases. SERMAS will normally refer to a second consultant within the public network. In practice the process is administrative and can take several weeks.
Comunidad Valenciana
Valencia's Ley 10/2014 de Salud and related decrees recognise the second opinion right in the public system, particularly for severe diagnoses and where treatment carries significant risk. The Valencian Conselleria de Sanitat handles requests through the patient's reference hospital.
Cataluña
Catalonia codified the right in Decret 35/2018, covering oncological diagnoses, treatments with severe or irreversible side effects, rare diseases and decisions affecting paediatric patients. The CatSalut system administers requests. Catalonia is often cited as having one of the most patient-friendly second opinion frameworks in Spain.
The umbrella body that lobbies on these issues is the Foro Español de Pacientes and the broader patient federation network. If you encounter pushback from a public hospital, escalating in writing — and copying the regional health ombudsman — usually opens doors.
3. When a second opinion makes real sense
Second opinions aren't free in administrative time, and not every diagnosis warrants one. The categories where they genuinely change outcomes are well established in the medical literature:
- Oncology — confirmed or suspected cancer, particularly rare cancers, complex stagings, or where multiple treatment modalities (surgery vs radiotherapy vs immunotherapy) are on the table.
- Neurosurgery — brain tumour resection, spinal surgery, decisions about Parkinson's deep brain stimulation, paediatric neurology.
- Cardiac surgery — valve replacement, complex bypass, congenital heart conditions, decisions between surgical and percutaneous approaches.
- Major orthopaedic surgery — bilateral joint replacements, revision surgery, spinal fusion.
- Organ transplant evaluations and complex transplant decisions.
- Rare diseases with fewer than 5 in 10,000 affected — diagnostic accuracy is often improved by specialist review.
- Paediatric serious illness — most parents want a second view, and most insurers and public systems support it.
- Treatments with severe, irreversible side effects — fertility-ending chemotherapy in young adults, for example.
Studies from US and European centres consistently find that 10–30% of second opinions in serious-illness contexts change the diagnosis or the recommended treatment in clinically meaningful ways. It's not a vote of no confidence — it's good medicine.
4. Getting a second opinion in the public system
If you're treated through the SNS, the route depends on your region but the structure is similar:
- Request your medical history. Submit a written request (solicitud de historia clínica) to your hospital's patient services office (Servicio de Atención al Paciente, often abbreviated SAP). Under Ley 41/2002 they must provide it within a reasonable period — practice ranges from a few days to a month.
- File a formal second-opinion request. In regions with codified rights (Andalucía, Madrid, Valencia, Cataluña and others) there's a specific form. Elsewhere, a written letter citing Ley 41/2002 and the serious nature of the diagnosis usually works.
- Wait for a designated second specialist. The regional health authority assigns a consultant at a different hospital. You attend a consultation, hand over your file, and receive a written report.
- Decide. The two opinions may agree or disagree. Either way, you choose which path to follow — you can't usually combine treatments from two different public hospitals, but you can switch your reference hospital with paperwork.
5. Sanitas Segunda Opinión — how it works
Sanitas Segunda Opinión Médica Internacional is one of the strongest benefits in the Spanish private market — and one of the most under-used. It's included as standard in Sanitas Más Salud, Sanitas Más 100, Sanitas Premium and most professional and family tiers. Customers don't pay extra.
What it covers
Sanitas contracts with a network of leading international medical centres to provide written second opinions for a defined set of serious diagnoses. The categories typically include:
- Malignant tumours (confirmed cancer of any kind)
- Major neurosurgical procedures (brain and spinal tumours, complex cranial surgery)
- Cardiac surgery, including bypass, valve replacement and congenital heart disease
- Organ and bone marrow transplants
- Severe burns, acute renal failure, multiple sclerosis, ALS and certain rare neurological conditions
- Coma states
How to invoke it
- Call Sanitas customer service or open a request through the Mi Sanitas app — there's a specific Segunda Opinión Médica option.
- A case manager (often medically trained) walks you through the process in Spanish or English.
- You sign authorisations and supply your full medical record (Sanitas can help collect it from in-network providers).
- Sanitas translates the file as needed and sends it to the specialist centre that best matches your condition.
- An expert produces a written report — usually within 10–15 working days — translated back into Spanish (and English on request).
- Your case manager talks you through the findings. There's no obligation to follow them.
Crucially, Sanitas's network typically includes MD Anderson Cancer Center Madrid (the European sister to MD Anderson Houston) and partners with internationally renowned centres for non-oncological cases. For Bupa-tier customers, the global Bupa network of expert hospitals is also accessible.
6. Caser Segunda Opinión Médica — how it works
Caser Segunda Opinión Médica Internacional is structurally similar and offered as standard on most Caser Activa, Caser Premium and family policies. Caser partners with the international network Best Doctors — a curated database of more than 50,000 peer-nominated specialists worldwide — to provide expert review for serious illness.
What it covers
The eligibility list is broadly comparable to Sanitas, covering oncology, neurosurgery, cardiac surgery, organ transplant decisions, severe injury, rare disease and life-threatening neurological conditions. Caser's published material highlights:
- InterConsultation — a written second opinion from a leading global specialist
- FindBestDoc — help identifying the right specialist anywhere in the world if you want to travel for treatment
- FindBestCare — coordination of care abroad if you choose to be treated outside Spain
- Ask the Expert — for non-life-threatening but still important medical questions
How to invoke it
- Contact Caser customer service or use the policy app to open a Segunda Opinión Médica request.
- A Best Doctors case manager — usually a registered nurse — takes over the case.
- You provide authorisations and your medical record. Best Doctors will chase missing pieces directly with your hospitals.
- The case is matched to one or more peer-nominated specialists worldwide; pathology slides and imaging are often re-read by leading centres as part of the process.
- A consolidated written opinion is produced — typically within 2–3 weeks of complete documentation arriving — translated into Spanish.
- The case manager debriefs you on the findings and answers questions.
Caser's Best Doctors partnership means the opinion can draw on specialists from MD Anderson, Memorial Sloan Kettering, the Mayo Clinic, Johns Hopkins, the Cleveland Clinic and dozens of leading European centres, including specialists in the UK, Germany and France — which is particularly reassuring for expats who want a view from a doctor in their home country's medical system.
7. Best Doctors, MD Anderson and the international network
Two names dominate the international second-opinion landscape in Spain. Knowing what each one actually does helps you understand what your policy is offering.
Best Doctors
Best Doctors (now part of Teladoc Health) is essentially a peer-curated specialist directory — built from confidential surveys asking specialists "if you or a loved one needed care in your specialty, who would you choose?" The result is a network of doctors nominated by their peers, organised by sub-specialty. When you trigger a second-opinion case through Caser (and through some Sanitas tiers), Best Doctors clinicians match your case to the right names in the network and coordinate the review. It's a service, not a single hospital.
MD Anderson Madrid
MD Anderson Cancer Center Madrid is the Spanish sister centre of MD Anderson Cancer Center Houston — one of the world's most renowned cancer hospitals. The Madrid centre operates clinically in Spain, treating both Spanish public-system referrals and private patients. For oncology second opinions through Sanitas (and via Best Doctors where MD Anderson specialists are involved), it functions as a tier-one expert review centre. Many of its multidisciplinary tumour boards include consultation with the Houston centre on complex cases.
Other partner centres you may encounter
Depending on the diagnosis and policy, second-opinion files can be reviewed at: Clínica Universidad de Navarra (CUN), Hospital Universitario La Paz (public, but reachable through some private second-opinion processes), Memorial Sloan Kettering, the Mayo Clinic, Hospital for Sick Children (Toronto) for paediatric cases, and major European cancer centres in Germany, France and the UK. Your case manager will tell you where the file is going before they send it.
8. The documentation you'll need
The quality of a second opinion is entirely dependent on the quality of the file the specialist receives. A rushed second opinion based on a one-page summary is almost worthless. Here's what to gather, in the order you'll need it.
Core medical record
- Informe clínico de alta or full informe médico from the treating consultant, dated and signed.
- Pathology reports (anatomía patológica) — if cancer is involved, these are non-negotiable. The physical pathology slides and blocks may need to travel too.
- Imaging — original DICOM files of MRI, CT, PET and ultrasounds, not just the radiologist's report. Hospitals will burn a CD or provide a download link.
- Lab results — blood work, tumour markers, hormonal panels, anything relevant.
- Cardiac investigations if relevant — ECGs, echocardiograms, angiography reports and videos.
- Surgical reports (protocolo quirúrgico) for any previous procedures.
Personal context
- Medication list with doses, including over-the-counter and supplements.
- Personal medical history — chronic conditions, previous surgeries, allergies.
- Family medical history — particularly important for cancer and cardiac second opinions.
- The specific question you want the second opinion to answer. "Should I have this operation?" is broader than "Is laparoscopic resection a safer option than open surgery in my case?" — and broader questions get broader answers.
9. Timelines — how long the process takes
How quickly you can have a written second opinion in your hands depends almost entirely on (a) the route you use and (b) how complete your documentation is on day one.
| Route | Typical timeline | What slows it down |
|---|---|---|
| Public system (regional) | 4–10 weeks | Administrative processing, specialist availability |
| Sanitas Segunda Opinión Internacional | 10–20 working days | Pathology slide transport, missing scans |
| Caser / Best Doctors | 2–4 weeks | Documentation gathering, translations |
| Out-of-pocket private (e.g. direct MD Anderson) | 1–6 weeks depending on centre | Initial appointment, scan re-reads |
| Informal in-person second opinion (paying privately for a single consultation) | 1–2 weeks | Specialist diary, file preparation |
The shortest realistic time-to-second-opinion in serious diagnoses is typically the private insurance route — both because the network is set up to move quickly and because the case managers actively chase paperwork on your behalf.
10. Common pitfalls expats run into
Not knowing the benefit exists
The single biggest pitfall. Sanitas and Caser both include international second opinion as standard on most policies, yet a survey of expat policyholders consistently shows that fewer than one in five know about it before a diagnosis hits. Check your policy schedule today — search for "segunda opinión".
Waiting too long to invoke it
Once a treatment plan is in motion — surgery scheduled, chemotherapy started — a second opinion becomes much harder to act on. The window to use a second opinion meaningfully is usually after diagnosis but before irreversible decisions. If your treating doctor is rushing you, ask politely for two weeks to seek a second opinion. That's almost always granted.
Asking the wrong question
"Do I have cancer?" is rarely the useful question. By the time you're seeking a second opinion, biopsy results have usually answered that. The useful questions are about treatment choice: "Is the recommended therapy the best option for my profile?", "Are there clinical trials I'd qualify for?", "What would the survival difference be between the two recommended approaches?"
Bringing only summary documents
A radiologist's report is not the imaging. A pathology summary is not the pathology slides. Specialists doing a second opinion want raw materials they can re-read, not pre-digested conclusions. Always ask your hospital for the originals.
Ignoring the regional rules
If you're in the Andalusian, Madrid, Valencian or Catalan public systems, there's a defined administrative path. Going outside it (e.g. asking the consultant directly for a colleague to look at the case) sometimes works, but it's not the path you're entitled to use. If something matters, file the formal request in writing.
Treating it as confrontational
Spanish consultants are, as a rule, supportive of second opinions when handled professionally. The line is simple: "Doctor, given how serious this is, my family and I want to invoke our right to a second opinion through my Sanitas policy before deciding. Would you be willing to share the full file?" In 99% of cases the answer is yes and the relationship is unchanged.
11. Choosing a policy with strong second-opinion cover
If you're shopping for private health insurance in Spain and second-opinion access matters to you, two policies stand out and they cover the market between them.
Sanitas
Sanitas Segunda Opinión Médica Internacional is included as standard on the Más Salud, Más 100 and Premium tiers, and on most professional and family policies. Sanitas is owned by Bupa, which gives Premium-tier policyholders access to a broader global expert network. Particularly strong for oncology second opinions through the MD Anderson Madrid relationship. Best fit: expats based in Madrid, Barcelona and the Costa del Sol who value strong English-language case management.
Caser
Caser Segunda Opinión Médica Internacional, delivered through Best Doctors, is bundled into the Activa, Premium and family product ranges. Best Doctors' peer-nominated network is broader by number of specialists and offers an unusually wide international panel, which appeals to British and Irish expats who appreciate the option of an opinion from a UK or Irish consultant. Best fit: expats anywhere in Spain who want maximum flexibility on the country of the second-opinion specialist.
Both policies include the second-opinion benefit at no extra premium when it's part of the underlying plan — but the eligible conditions and the network differ. We'll always check the current policy schedule for you before you commit.
Want a policy that includes international second-opinion cover?
We arrange Sanitas and Caser private health policies for British, Irish, American and northern European expats living in Spain. Both include international second medical opinion at no extra cost on the right tier — a 10-minute call confirms which fits your situation best.
Get a Health Insurance Quote12. Frequently asked questions
- Do I have a legal right to a second medical opinion in Spain?
- Yes — but in two layers. At national level, Ley 41/2002 establishes the right to information and to a copy of your medical history, which together make a second opinion possible. At regional level, Andalucía, Madrid, Comunidad Valenciana, Cataluña and several other autonomous communities have codified an explicit right to a second opinion in defined serious-illness contexts, with administrative procedures to invoke it.
- Will my Spanish doctor be offended if I ask for a second opinion?
- Very rarely. Most Spanish consultants are familiar with second-opinion requests, especially in oncology, neurosurgery and cardiac surgery. Frame it as part of an informed decision rather than a challenge to their competence. Asking for a copy of the file is your legal right under Ley 41/2002.
- Does Sanitas pay for the international second opinion entirely?
- On the policies where Segunda Opinión Médica Internacional is included as a benefit, yes — Sanitas pays the international centre directly, and you pay nothing for the review. Travel for in-person consultations or treatment abroad is a separate question and is not normally covered unless your policy specifically extends to it.
- Does Caser cover treatment abroad if Best Doctors recommends it?
- The Best Doctors written opinion and case-management service are covered. Treatment abroad on the back of that opinion is a different policy section — Caser's FindBestCare coordinates it but most policies require treatment to take place in Spain unless you have an international or reembolso rider. Read your specific schedule.
- How long does the Sanitas or Caser second-opinion process take?
- From the day complete documentation reaches the international centre, expect a written opinion within 10–15 working days for Sanitas and 2–3 weeks for Caser / Best Doctors. The total time from request to decision is usually 3–5 weeks because most cases need additional paperwork or scan re-reads.
- Can I use a second opinion to switch my surgeon or treatment plan?
- Yes — that's the whole point. The written second opinion is yours to act on. You can take it to your existing treating doctor (most are open to discussing it), switch to another consultant within your network, or in some cases travel abroad for treatment if your policy allows it.
- What if my diagnosis isn't on the eligible list?
- Both Sanitas and Caser publish a defined list of conditions for the international second opinion — generally limited to serious, life-threatening or life-altering diagnoses. For non-listed conditions you can still get a second opinion from another consultant within your private network at no extra cost, or pay privately for an out-of-network specialist consultation (usually €100–€250).
- Where do I find the official list of eligible conditions for my policy?
- In your policy schedule (condiciones particulares) and on Sanitas's or Caser's customer portal. If you can't find it, call the customer line and ask them to email the up-to-date list — they're obliged to provide it. Eligibility is occasionally updated, so check the current version rather than relying on a brochure that may be a few years old.
This guide is general information only and does not constitute insurance, medical or legal advice. Policy terms, eligibility lists and regional patient-rights regulations change — always verify current details with the insurer, hospital or relevant regional health authority before relying on them. 247 Expat Insurance is an introducer of regulated UK and Spanish insurance products.