Before bidding in a Spanish public auction, you need to know which right is being sold, which charges survive and when you must pay. This guide answers 55 common questions, grouped so you can check the main risks before committing funds.
At Subastic, we have prepared this guide to answer common questions about Spanish public auctions. The answers are checked against the official sources linked below and provide practical criteria for assessing a potential purchase.
Reviewed on 12 November 2026. The 2025 judicial reform has transitional rules: the auction’s publication date alone does not identify the law that applies. Read the notice and case file before using any percentage or deadline.
1. Getting started
1. Who can participate in an auction?
You do not need to be a professional auction bidder. You must be legally entitled to acquire the asset, be free of any applicable prohibition and meet the procedure’s identification, representation and deposit requirements. On BOE, browsing notices and registering to bid are separate steps. A Subastic account does not replace registration on the source portal.
2. What discount can you realistically achieve?
There is no guaranteed discount. Compare the total acquisition cost with market transactions involving equivalent assets, allowing for condition, charges and possession. Auction value may be outdated and is not a market price. A low bid can become expensive if a prior mortgage survives or litigation is needed.
3. How should you respond to pressure or suspected collusion?
Electronic bidding does not establish that every unlawful practice has disappeared. Do not accept payment to stop bidding or enter agreements to manipulate the result. Keep messages and report threats or suspected interference to the managing authority and, where appropriate, the competent authorities.
4. What is a sensible first step?
Study several auctions before bidding: identify the asset and the right being sold, read the notice and charges certificate, and prepare a budget. A garage or storage room may require less capital but can still have access, identification or ownership problems. Choose a clear case file rather than simply a low price.
5. How much capital do I need, and what return can I expect?
You need liquidity for the deposit and the balance within the payment deadline, plus taxes, expenses and contingencies. If awarded the lot, your deposit counts towards the price: do not count it twice. Calculate returns after all costs and any period without income. There is no universal minimum investment or return.
6. Where are auctions published?
The BOE Auction Portal hosts several judicial, notarial and administrative procedures. Social Security and other channels also publish on their own portals; insolvency sales may use specialist entities. Subastic aggregates several sources to help you search. Always check the documents and participation conditions at each auction’s source.
7. Is there a better time of year to buy?
No season guarantees less competition or better prices. Assess each case on its conditions and your ability to investigate and pay. Holidays and professional availability can make checks and paperwork harder; do not assume that they suspend a deadline stated in the notice.
Official references: BOE Auction Portal FAQ; Criminal Code, Article 262; Civil Procedure Act; Tax Agency: awards and paperwork; Social Security Collection Regulation; Insolvency Act; Organic Law 1/2025: reform and transitional rules.
2. Auction types and award thresholds
8. How do appraisal, auction value and the claimed debt differ?
An appraisal is a valuation; auction value is the procedure’s reference amount; and the claimed debt belongs to the enforcement proceedings. They can differ considerably. Also check whether the lot contains one asset or several: a lot value is not a separate price for every asset.
9. What does the 70% threshold mean in a judicial auction?
In judicial enforcement involving real estate, 70% is a threshold relevant to approval of the winning bid, not a requirement to bid exactly that percentage. Lower offers trigger additional rules, with specific protections for a debtor’s habitual residence. Article 670 changed in 2025: identify the version applicable to the proceedings before calculating a bid. For example, 70% of a €100,000 auction value is €70,000; that calculation excludes taxes and surviving charges.
10. Does covering the claimed debt guarantee an award?
No. Covering the debt can matter under particular approval rules, but it does not replace applicable thresholds, debtor safeguards or procedural decisions. It may not cover interest and enforcement costs either. Analyse the specific case rather than treating the claimed debt as an automatic minimum purchase price.
11. How does the 50% threshold work in Tax Agency auctions?
Under the general tax collection rules, a highest bid of at least 50% of the auction reference value qualifies for award under the auction board’s rules. Below that level, the board assesses whether the offer is sufficient; there is no automatic right to buy. A returned deposit does not itself establish a portal error.
12. Do Social Security auctions follow the same rules?
Do not transfer Tax Agency or judicial enforcement percentages and deadlines to Social Security auctions. Its collection regulation governs deposits, bids, awards and payment, and was amended in 2026. Check the notice and the applicable version of the rules: examples published before the amendment may describe an earlier system. The regulation distinguishes 25% deposits for sealed offers and 30% for oral participation, with separate award rules.
13. What is different about voluntary auctions?
A voluntary auction is not equivalent to enforcement for unpaid debt. The approved conditions and the judicial or notarial route determine how assets are offered and results accepted. Check reserve prices, the applicant’s powers, charges and expenses. Do not assume that mortgages will be cancelled as they might be in particular enforcement proceedings.
14. What should I check in an insolvency auction?
Read the liquidation rules and sale conditions, including any required court approval. Check whether the sale concerns an individual asset or a business unit, who pays expenses and how secured rights are treated. Include any specialist entity’s commission and its calculation basis in your budget when the conditions require it.
15. What happens if nobody bids?
Under the reformed judicial regime, Article 671 does not automatically award the asset to the enforcing creditor after an auction without bidders: it provides other routes, including a debtor-designated third party or an agreed new sale. Other procedures and the earlier judicial regime differ. Check the managing authority’s decision; portal closure does not establish an award.
16. What changed with the 2025 efficiency reform?
Organic Law 1/2025 changed judicial auction rules, including deposits, bid information, approval and payment. Its transitional regime requires attention to when proceedings began, not simply the auction date. Do not combine a deposit from the old rules with a payment deadline from the new ones.
Official references: Civil Procedure Act; Organic Law 1/2025: reform and transitional rules; General Tax Collection Regulation; Tax Agency: awards and paperwork; Social Security Collection Regulation; Voluntary Jurisdiction Act; Insolvency Act.
3. Charges and registry checks
17. Can I rely on a portal showing zero charges?
That field is no substitute for checking the register and case file. It may not reflect current debts, statutory liabilities or occupation. Compare a recent registry extract with the ownership and charges certificate and enforcement documents. For vehicles, also obtain a DGT report and, where appropriate, check the Movable Property Registry.
18. Which charges can survive an award?
In judicial enforcement, charges ranking ahead of the enforced charge generally survive; cancelling the enforced and later entries requires the relevant title and registry order. Registry priority matters more than the creditor’s identity. Community fees, taxes and occupation rights require additional analysis: ranking mortgages alone does not settle them.
19. How do I identify the charge being enforced?
Match the notice and case number with the registry certificate and marginal notes recording its issue. If documents are missing or inconsistent, ask the managing authority and registry for clarification. Auction value or the creditor’s name can guide your enquiries but do not independently prove which registered charge is being enforced.
20. What if the same bank holds two mortgages and enforces the second?
The first mortgage does not disappear merely because the creditor is the same. If it has priority and no applicable ground for cancellation exists, it can survive enforcement of the second. Check its balance, ranking, amendments and any allocation of secured liability before calculating your total cost.
21. How should charges with equal priority be assessed?
Do not automatically treat them as later charges that will be cancelled. Equal priority may arise from registered agreements whose terms affect enforcement. Have the entries and proposed cancellation order reviewed; uncertainty over which rights survive should be resolved before bidding.
22. Must I pay the debtor’s entire outstanding debt?
Buying an asset through enforcement does not by itself make you personally liable for the debtor’s entire claim. You must pay the price and account for surviving charges and statutory obligations. A €2.4 million debt and €200,000 auction value are not enough to price the purchase: identify the enforced right and any rights ranking ahead of it.
23. What happens to a prior mortgage in a Tax Agency auction?
A prior mortgage can survive when the Tax Agency sells real estate under a later tax attachment. Verify priority and the current balance using adequate documents. The amount in the notice is not necessarily the redemption balance; include that risk in your budget and establish how the security could be discharged.
24. What does a tax liability notice in the registry mean?
It can warn that the asset is legally exposed to certain tax obligations connected with a transfer. It does not by itself establish an enforceable debt in the stated amount. Check the tax, transaction, dates and any assessments or reviews; do not treat it as an ordinary mortgage.
25. Does an old or matured mortgage cancel itself?
Loan maturity and removal of a registered mortgage are different matters. Cancellation may require creditor consent, a court decision or an application satisfying statutory time limits and conditions. Do not disregard an entry solely because it is old: ask the registry to confirm the applicable cancellation route.
Official references: Civil Procedure Act; Mortgage Act; DGT: vehicle transfers and checks; General Tax Collection Regulation; General Tax Act, limitation and asset liability; Transfer Tax and Stamp Duty Act, Articles 7 and 10.
4. Deposits, bidding and payment
26. How much is the deposit, and when is it returned?
Check the deposit required in the notice. For judicial real estate auctions subject to the new wording of Article 669, the reference is 20%, with a €1,000 minimum and scope for judicial adjustment; other regimes differ. Refunds depend on the result and whether you reserved your bid. The successful bidder’s deposit counts towards the price. Under the Tax Agency’s general rules, the deposit is 5% of the auction reference value.
27. What does reserving a bid mean?
It keeps your offer available for consideration if the highest bidder defaults, under the applicable rules. In exchange, your deposit can remain blocked and an award may come later. Before agreeing, check the ranking of reserved bids and whether you can keep the balance available during that wait.
28. Should I bid early or late?
No timing guarantees an advantage. Bid visibility and closing rules vary with the procedure and its transitional regime. Read the conditions and avoid relying on the last seconds: connection or identification failures do not guarantee reopening. Set your maximum beforehand and do not increase it under competitive pressure.
29. What happens if the highest bidder fails to pay?
The bidder can lose the deposit and trigger the consequences of auction default, potentially including consideration of reserved bids or further proceedings. An unusually high offer does not itself prove fraud, but it does not remove your obligations as a bidder either. Never bid beyond the funds or financing you can secure within the deadline.
30. How long do I have to pay the balance?
It depends on the procedure and applicable law. For judicial real estate auctions under the 2025 reform, Article 670 provides twenty days from closure for the approval scenario in its first paragraph; the earlier regime used a different period and starting point. Confirm the triggering event and payment instructions for the specific case in writing. The Tax Agency’s rule is fifteen days from notification; Social Security’s is five working days.
31. Can I finance the purchase with a mortgage?
It may be possible, but approval, valuation and completion must fit the payment deadline and available title. An indicative preapproval does not guarantee funds will arrive in time. Discuss auction-specific requirements with the lender and arrange alternative liquidity before depositing; failed financing does not automatically release you from payment.
32. How long does final adjudication take?
Bidding closure, approval, the award decree, registration and delivery of possession are separate milestones. Procedural issues or missing documents can delay them. Do not forecast rental or resale dates from bidding closure alone: check the case status and budget for a period without income.
Official references: Organic Law 1/2025: reform and transitional rules; BOE Auction Portal FAQ; General Tax Collection Regulation; Social Security Collection Regulation; Civil Procedure Act; Criminal Code, Article 262; Tax Agency: awards and paperwork; Mortgage Act.
5. Possession, occupants and habitual residence
33. How can I investigate real estate that I cannot inspect?
Compare registry, cadastre, case documents and planning information, checking they describe the same property. Request a visit through the authorised route and establish access limitations. Photographs and an external inspection do not prove interior condition or vacancy. Budget for repairs and uncertainty when verification is impossible.
34. What protection can apply to a habitual residence?
Law 1/2013 provides for suspension of certain evictions from habitual residences in specified circumstances, subject to eligibility and statutory duration. It does not automatically protect every occupied home or every award. Check vulnerability requirements, the procedure and case decisions; your bid amount alone does not establish when possession will be available.
35. Should I negotiate with the occupants?
An agreement can facilitate voluntary handover, but verify who occupies the property, their legal basis and who can validly agree. Record obligations, the handover date and any payment, preferably linked to actual delivery. Avoid pressure or promises of guaranteed results; assess the agreement with professional advice and complete any necessary formalities.
36. Does a tenancy survive the auction?
It depends on the contract, its date, registration where relevant and the applicable legislation. A statement that occupants have a right to remain requires examination of the decision and underlying title. An award does not authorise you to ignore a surviving tenancy. Check duration, rent and recovery options before forecasting returns.
37. What if a court order does not recognise an occupant as a tenant?
Read precisely what the order decides, whom it binds, whether it is final and which route to possession it permits. It does not automatically make the property available or authorise private eviction. Obtain the full decision and confirm outstanding steps with a professional familiar with the case.
38. Will the Tax Agency or Social Security deliver vacant possession?
Do not assume an administrative award includes judicial eviction of occupants. Acquisition of title and physical recovery of possession are separate issues. Check the conditions and occupation status; if voluntary handover is unavailable, a separate procedure may be necessary, with its own costs and timescale.
39. Can I simply change the locks?
Do not use lock changes, entry without consent or disconnection of utilities to remove occupants. Ownership does not replace legal requirements for access and recovery of possession. Document a valid voluntary handover or use the appropriate judicial route before acting.
Official references: Civil Procedure Act; BOE Auction Portal FAQ; Law 1/2013, Article 1; Civil Code: shared ownership and usufruct; Urban Leases Act, Article 13; General Tax Collection Regulation; Social Security Collection Regulation; Criminal Code, Article 262.
6. Shared ownership, bare ownership and bid assignment
40. What am I buying if 50% of a property is auctioned?
You generally acquire an undivided ownership share, not a physical half or exclusive use. You must account for the other owners, use agreements, expenses and possible co-owner redemption rights. A garage share can have a particular registry structure: check whether use of a specific parking space is attached to it.
41. What does buying bare ownership mean?
You acquire ownership subject to a separate usufruct, so use and income may belong to the usufructuary until that right ends. Check duration, holders and allocation of expenses. Do not assume immediate rental income or value the purchase as vacant full ownership.
42. Can I force the sale of an inheritance or jointly owned property?
Division of jointly owned property and partition of an inheritance have different procedures and requirements. An indivisible asset may ultimately be sold if no agreement is reached, but buying a share does not guarantee an immediate sale or your expected price. Assess litigation, indivision agreements and costs first.
43. What is assignment of a winning bid, and who can do it?
It is a procedural mechanism allowing a third party to take the successful bidder’s position where legislation permits. It is not a general entitlement for every bidder: check who may reserve assignment, the deadlines and required formalities. Also assess taxes, charges and possession; assignment does not itself remove a debtor or occupant. In judicial enforcement, Article 647 reserves this option to the enforcing creditor and subsequent creditors.
Official references: Civil Code: shared ownership and usufruct; Voluntary Jurisdiction Act; Civil Procedure Act; Social Security Collection Regulation.
7. Expenses and taxes
44. How do I prepare a complete budget?
Add the price, surviving charges, taxes, registry fees, professional advice, any commissions, repairs, possession costs and financing. Purely illustratively: €80,000 price + €15,000 prior charge + €6,000 estimated taxes + €9,000 other costs and contingency = €110,000. Replace each assumption with verified amounts; the example does not establish a tax rate.
45. Is transfer tax always payable, and on what amount?
No. Depending on the asset, transferor and transaction, transfer tax or VAT may apply, together with stamp duty where relevant. For real estate, the cadastral reference value can affect the taxable base: the winning bid alone does not always determine it. Confirm the tax, base, reliefs and filing deadline with the competent tax authority.
46. Who is responsible for community fees and property tax arrears?
Under the state horizontal property regime, the property is liable for community fees for the current year and previous three calendar years; check the applicable civil law. IBI property tax has separate asset liability, assessment and limitation rules. Obtain certificates and assessments: do not apply the three-year rule universally to taxes.
47. Is a public deed required for a Tax Agency award?
The regulation allows registration using the administrative award certificate and relevant cancellation documents, without a public deed always being necessary. Check the specific title requirements, tax filing and registry requirements. Do not extend this answer to every voluntary or insolvency sale.
48. Must an award be registered?
Registration is generally not what creates ownership on acquisition, but it is essential for registry protection and later transactions such as a mortgage. Check any case-specific requirements and lodge the title promptly. Leaving an award unregistered can weaken protection against third parties and complicate future transfers.
49. How do I calculate a gain on resale?
Distinguish economic profit from taxable gain. For an individual, the personal income tax capital gain uses disposal and acquisition values adjusted under the legislation, including eligible expenses and depreciation where applicable. Municipal land value tax has separate rules. A company or business activity may receive different tax treatment.
Official references: Transfer Tax and Stamp Duty Act, Articles 7 and 10; Tax Agency: awards and paperwork; VAT Act; Catalan Tax Agency: taxable base, including auctions; Horizontal Property Act, Article 9; Local Treasury Act, Articles 64 and 99; General Tax Act, limitation and asset liability; General Tax Collection Regulation; Mortgage Act; Personal Income Tax Act, Articles 33–35.
8. Vehicles, garages and storage rooms
50. What specific risks arise when buying a vehicle?
Check identity and chassis number, the DGT report, charges, transfer eligibility, roadworthiness inspection, keys and mechanical condition. Include transport, storage, repairs and taxes. Lack of a test drive increases uncertainty. A low price does not compensate for a vehicle you cannot transfer or whose roadworthy condition costs are unknown.
51. What happens to unpaid vehicle tax?
Check vehicle tax (IVTM) and its effect on ownership transfer with the municipality and DGT. An earlier unpaid bill does not automatically make you liable for all the previous owner’s personal debts, but it can create an administrative obstacle. Identify the tax year, liable taxpayer and required documents before assuming transfer is possible.
52. How do I check that a garage or storage room exists and is usable?
Compare registry identity, cadastral reference, plans, numbering and physical access. Confirm whether the sale concerns a separate property, an accessory space or a share carrying allocated use. Check dimensions, vehicle access and planning status; a registry description does not guarantee a space is marked, built or available in practice.
Official references: DGT: vehicle transfers and checks; DGT: transfer instruction including auctions; Local Treasury Act, Articles 64 and 99; Mortgage Act; Civil Code: shared ownership and usufruct.
9. Mistakes and practices to avoid
53. Can I coordinate bids with a partner?
Joint acquisition and lawful representation differ from arrangements to manipulate prices or exclude bidders. Article 262 of the Criminal Code penalises specified conduct interfering with public tenders and auctions. Do not use separate accounts to simulate competition or carry out an unlawful agreement; document the purchase structure transparently.
54. What should I check if a website or professional bids for me?
Verify identity, authority to represent you, fees, custody of funds, bidding limit and responsibility for errors. Confirm who will be recorded as bidder and successful purchaser and how you receive evidence. Do not share personal credentials or accept guaranteed-award promises. Search or intermediary services do not replace the managing authority’s conditions.
55. Can I use AI to decide a bid?
AI can help organise documents and prepare questions, but it can also confuse procedures, invent rules or apply repealed versions. Check every conclusion against the case file and official sources, especially charges, taxes and deadlines. Before deciding a bid, obtain professional review of issues affecting maximum loss and the ability to obtain possession.
Official references: Criminal Code, Article 262; BOE Auction Portal FAQ; Civil Procedure Act; Organic Law 1/2025: reform and transitional rules.
Before placing a bid
Identify the asset and right, verify charges and possession, confirm deposit and payment rules, and set a maximum based on the total cost. If a material uncertainty remains, resolve it before bidding. This guide provides general information; legal and tax decisions require review of your specific case.
Use Subastic’s search to compare assets and our sources page to identify the originating portal. Bids and deposits are handled by the source, under the conditions set by the managing authority.
Written by
Subastic editorial team