A father once told me that the most valuable thing he was leaving his children didn't fit in the deed. I nodded, the way you nod at a nice line over a work lunch. Years later, I've come to understand he wasn't exaggerating. If anything, he undersold it.
Let's start with the facts, because that's what they're for: since 2 July, the Region of Madrid grants a 99% rebate on inheritance and gift tax when what's being transferred is a family business. Law 3/2026 carries the polished name "Support for the Family Business," but translated into plain English, here's what it actually does: if you meet the set of requirements the law lays out — which I won't detail here, because they're technical and depend on each case — 99% of the business's value falls outside the tax base. The treasury only looks at the remaining 1%. (One catch: it's incompatible with the state-level 95% relief under Article 20.6 of the Spanish Inheritance and Gift Tax Act — you pick one, not both, like a buffet with grandmother's house rules.)
That's genuinely good news. Many families had been postponing the handover for years because the tax bill scared them more than the succession itself. Now it's less frightening. So more of them will move.
And this is where I come back to the father and the deed. Because the day that handover actually happens — or the day a buyer shows up, or the day a cousin wants to cash out their share and someone has to put a number on forty years of work — it won't be the notary who decides what the business is worth. It'll be a data room.
A data room is, essentially, a shared folder where everything that "proves" a business's value gets dropped in. And that's exactly where the problem starts, because what actually holds up 60% to 90% of a family business's value almost never fits in a shared folder. It lives in the founder's head, in the trust of a client who's only ever wanted to deal with one person for twenty years, in the son who learned to read a machine — or handle a difficult supplier — without anyone ever writing it down for him.
When someone opens that data room to put a price on the business, this is roughly what gets looked at, in this order:
- The usual numbers: balance sheet, accounts, debt. The easy part.
- The contracts: with clients, suppliers, key employees. This is where the pulse starts to race — how many of those contracts depend on a person rather than the company?
- Brand and intellectual property: is it registered, or does it just live in the reputation of a name on the door?
- Critical know-how: is it written down anywhere, or will it walk out the door with someone the day they retire?
- Customer concentration: if 40% of revenue depends on one personal relationship with the founder, that's not an asset. It's a risk wearing an asset's clothes.
None of this shows up on the balance sheet. Not because anyone's hiding it — simply because nobody ever put it there. And that's why, when it comes time to sell — or to divide things up — what usually brings the price down isn't that the business is failing. It's that nobody can prove what the value they're asking for is actually made of.
One figure to put this in context, because it matters here specifically: the Region of Madrid is home to 1 in 5 family businesses in all of Spain — more than one in five, according to the Region of Madrid itself (April 2026). And these family businesses aren't a footnote: they account for 58.9% of regional private employment and 46.2% of regional Gross Value Added, per the same official source. When generational handover moves in Madrid, a genuinely large slice of the real economy moves with it — not a handful of anecdotes.
The new law solves a real part of the problem: the cost of the handover. That's genuine relief, and anyone facing this move should talk to their tax adviser as soon as possible (I'm not one, and this isn't meant to be advice). The exact requirements and how long this relief stays in place can change; what counts here is the picture as it stood on the date this article was published.
But there's a question no law answers, because it isn't a tax question. It's the one asked by the buyer, the bank, or the cousin with a calculator, the day they sit down to price what your family built:
Which part of your sale price could you not defend?
Liliana Bolós helps family businesses and buyers put a name and a number on what the balance sheet doesn't show. This article is for informational purposes and reflects the regulation in force at the time of publication. It does not constitute personalised tax or legal advice, does not detail the full set of applicable requirements, and does not replace consulting a qualified tax adviser before making any decision about succession, gifting, or the transfer of a family business.