Bizkaia Tax Office
All about your procedures with the Bizkaia Tax Office: news, what each thing is and step-by-step guides.
What the Bizkaia Tax Office compliance certificate is and what it's for
The document that shows you don't owe the Tax Office anything. You're asked for it for grants, public contracts, subcontracting and banks.
Step-by-step guideHow to register as self-employed in Bizkaia, step by step
Tax Office and Social Security at once: what to decide first, what gets filed and what happens next.
Step-by-step guideCertificate of not having to file an income tax return in Bizkaia
Who needs it and how to request it: grants, benefits, renting or a mortgage.
ExplainedTax status certificate: what it says and how it differs from the compliance certificate
Two certificates that often get mixed up, explained in a minute.
Step-by-step guideIAE certificate in Bizkaia: how to prove you're registered
What you're asked for it for and how to get it.
ExplainedMy tax certificate came out negative: what it means and how to fix it
The most common reasons and what to do in each case.
ExplainedHow long a Tax Office certificate takes in Bizkaia and what it costs
Timeframes, price and how long it's accepted for.
ExplainedIAE registration in Bizkaia: when form 036 is enough
When the Tax Office alone is enough and when you also need Social Security.
Step-by-step guideWhich IAE heading applies to me: how to choose it properly
With examples of the most common jobs.
ExplainedHow much it costs to be self-employed in Bizkaia
Contribution by income band, taxes and costs worth bearing in mind.
ExplainedWhich VAT scheme do I have: standard, equivalence surcharge, exempt or módulos
How to know which one applies to you based on your activity.
ExplainedWorking from home or without premises: how to state it when you register
What goes on your Tax Office and Social Security registration if you have no premises.
ExplainedWhat a mutual insurer (mutua) is and which one to choose in Bizkaia
What it's for and why you have to choose one when you register.
ExplainedLoss of activity cover: unemployment benefit for the self-employed
What it is and whether it's worth paying for.
ExplainedIncome tax prepayment in Bizkaia: when you have to make it
Who has to do it and who doesn't.
Step-by-step guideI'm a foreigner: what I need to become self-employed in Bizkaia
NIE, work permit and Social Security number.
ExplainedWhat a Punto de Atención al Emprendedor is and what it does for you
Why with one you register with the Tax Office and Social Security at the same time.
ExplainedSelf-employed or limited company: which suits you when starting out
The differences that really matter, without jargon.
ExplainedWhat TicketBAI and BATUZ are and what changes when invoicing in Bizkaia
What you need to know before you issue your first invoice.
Step-by-step guideHow to change your tax address with the Bizkaia Tax Office
If you've moved, this is what you have to report and when.
Step-by-step guideHow to change your bank account with the Tax Office
For direct debits and refunds.
Step-by-step guideAdding or changing an activity when you're already self-employed
When you have to report it and what changes.
ExplainedHow to authorise someone to deal with the Tax Office for you
What voluntary representation is and how it's confirmed.
Step-by-step guideHow to withdraw an authorisation when you no longer want it
Step by step, on the online portal or with us.
Step-by-step guideI can't pay the Tax Office: how to ask for a deferral in Bizkaia
Which debts can be deferred and what you need.
ExplainedWhat the ROI is and when you need it
The register for selling to or buying from businesses in other EU countries.
Step-by-step guideHow to check whether an EU VAT number is valid in VIES
And why your client can't find you.
ExplainedInvoicing a client in another EU country
Intra-EU VAT made easy.
ExplainedAmazon, Google or Meta ask for your ROI number: here's why
What happens with VAT when you buy from European businesses.
Step-by-step guideHow to deregister from the ROI
When it makes sense and what happens next.
Step-by-step guideHow to deregister as self-employed in Bizkaia
Tax Office and Social Security, in the right order and without forgetting anything.
ExplainedWhat I have to file with the Tax Office after deregistering
The returns you still have to do.
ExplainedCan I stop for a few months without closing my activity?
The options available and what each one means.
Step-by-step guideTax calendar for the self-employed in Bizkaia
What's filed and when, month by month.
ExplainedBizkaia Tax Office or Spanish Tax Agency: what's the difference
Why in Bizkaia everything goes through the Bizkaia Tax Office.
Step-by-step guideHow to sign in to the Bizkaia Tax Office online portal
Digital certificate, B@kQ and other ways to sign in.
ExplainedThe most common mistakes when registering as self-employed
And how to avoid them from day one.
NewsMódulos in Bizkaia for 2026: which activities can use the simplified scheme
The provincial order that sets the activities and how to know if yours is included.
NewsSelf-employed flat rate in 2026: requirements and how much you pay
Who can apply and how long it lasts.
NewsSelf-employed contributions in 2026: the table by income band
How much you pay based on what you earn.
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