The best practice-management software for Spanish law firms (2026)

First, the thing you should know: this guide is published by Mandato, which is one of the seven products in it. Discount it accordingly. What we can offer in exchange is a rule we have followed throughout, and which you can check by reading: each competitor is described first by what it does better, and where we have no verified public information, the sentence says so rather than implying a gap.

None of these tools is “the best”. They compete at different things, and a litigation practice in Zaragoza, a property boutique in Marbella and a twenty-lawyer firm with its own knowledge department should not choose the same one. The useful question is not which wins, but which wins for you.

The four criteria that decide it in Spain

Before looking at any brand, it helps to know what is being compared. In the Spanish market, four things separate these products far more than the length of their feature lists.

The connection to the Spanish administration. A firm in Spain does not live on a generic ecosystem of integrations: it lives on LexNET, the AEAT, the Catastro and the registries. Excellent software that does not receive LexNET notifications inside the matter forces you to run two systems in parallel. It is the criterion that decides the most choices and the one most often skipped in demos.

Coverage of the regional court systems. If you litigate in Aragón, Navarra, Cantabria, La Rioja or Catalonia, your working day runs through Avantius or eJusticia.cat, not only LexNET. It is a binary criterion: either the product covers them or it does not, and if it does not, almost nothing else matters.

VeriFactu, on its real calendar. Royal Decree-Law 15/2025 postponed the dates: 1 January 2027 for companies and 1 July 2027 for the self-employed and everyone else. 2026 is a voluntary period. This matters for buying: there is no immediate emergency, but there is a deadline, and you want the tool you choose now not to need replacing in eighteen months. We set it out in the VeriFactu guide.

Where the accounting lives. Some of these products keep tax accounting inside, with the official forms. Others — Mandato among them — export to an accounting tool and do not reinvent it. Neither is superior: it depends on whether your accountant sits inside or outside the firm, and switching models is a change of process, not a preference.

Aranzadi Fusión — if legal research is the work

Aranzadi’s database is the reference for legal research in Spain, and that is hard to overstate: case law, consolidated legislation, doctrine and precedents with Thomson Reuters’ editorial apparatus behind it. Fusión puts that database and the matter on the same screen.

Choose it if research is the centre of your work and Aranzadi’s library is something you would use daily. For an administrative-litigation or complex-tax practice, that integration is worth it on its own.

Think twice if what you need is management rather than research. You will be paying — and it is expensive — for a legal library you might open once a week. The honest question is whether you are paying for the database or the software. Full comparison →

Kleos — if the backing of a global group matters

Behind Kleos is Wolters Kluwer, with the solidity and continuity a global publishing group brings, the group’s own document ecosystem, and a guided implementation that a large firm genuinely values.

Choose it if your firm is large, you want a legal database integrated into the suite, and you would rather someone walked you through implementation. Institutional backing is not an empty argument when the software holds twenty years of matters.

Think twice if you are a three-to-ten-person firm that values agility and will not use the document ecosystem. Full comparison →

MN Program — if accounting and the regional systems go inside

MN Program has been in Spanish firms for decades for solid reasons: real procedural depth, integrated tax accounting with the official forms, and coverage of the regional justice systems.

Choose it if your firm is pure litigation, files its own tax forms — 111, 115, 130, 303 — without leaving the program, and works daily with Avantius or eJusticia.cat. In that profile it is hard to replace, and we are not going to pretend otherwise.

Think twice if you work in two languages or want AI inside the workflow rather than in a separate module. Full comparison →

Sudespacho — if close support is what holds you

Sudespacho has been in small and mid-sized firms for a long time, and its support is genuinely close: you call and someone who knows your firm answers, not a ticket queue. It understands the reality of the three-person firm in a provincial capital better than most newer products.

Choose it if the relationship with your supplier is what you value most and you work in Spanish with Spanish clients. When something breaks on a Friday afternoon, knowing who to call is worth money, and a pricing page cannot buy that.

Think twice if you need real bilingualism or AI in the matter: it is a product conceived in another decade, and it shows in daily use. Full comparison →

Ofionline — the other “programa de gestión” with LexNET

Ofionline presents itself as practice-management software for lawyers and procuradores, with a cloud matter manager, diary, document management, OCR and LexNET built in. It is the only one on this list that addresses the procurador explicitly — a profile the rest of the market ignores.

Choose it if you are a procurador or a mixed lawyer-procurador practice, a segment almost nobody else builds for.

Think twice if you need something we have not been able to verify publicly. Unlike the five above, we have no detailed comparison of Ofionline and we are not going to improvise one: what is said here comes from their own public description, and beyond that we have no verified information.

Clio — if your firm does not practise in Spain

Clio is an excellent product and probably the best in the world in its category: an enormous integration ecosystem, serious analytics, and a user experience the Spanish market has nothing to match.

Choose it if your practice is international and does not depend on the Spanish administration, or if the integration ecosystem is your main criterion.

Think twice if you practise in Spain. Clio does not connect to LexNET, has nothing to say about VeriFactu, and its templates are not written in legal Spanish. That is not a flaw in the product: Spain is not its market. Full comparison →

Mandato — if you work in two languages and want AI inside the matter

Our turn, and the same rule applies. Mandato receives LexNET notifications into the matter with the deadline calculated, files submissions from the matter itself, queries the Catastro and the registries, invoices with chained records and a QR ready for VeriFactu, carries WhatsApp Business tied to the matter via 360dialog, and has AI inside the workflow — not in a separate tab. It runs in Spanish and English across the product, the templates and the client portal. The price is published.

Think twice if you litigate daily in Aragón, Navarra or Catalonia: we do not cover Avantius or eJusticia.cat, they are on the roadmap, and a roadmap is not an integration. If your tax accountant sits inside the firm, we are not your tool either: we export to Holded and the books live there. And we have neither Aranzadi’s library, nor Clio’s ecosystem, nor Kleos’s twenty years.

In one table

Product	Its strength	Where it doesn’t fit
Aranzadi Fusión	The legal-research library	If you only need management, you pay for the database
Kleos	Group backing and guided implementation	Small firms that value agility
MN Program	Accounting with tax forms, and regional systems	Bilingualism and AI in the workflow
Sudespacho	Close, direct support	A product of another decade in daily use
Ofionline	Lawyers and procuradores, with LexNET	No detailed comparison from us
Clio	World-class ecosystem and analytics	Doesn’t talk to LexNET, AEAT or VeriFactu
Mandato	Spanish administration, AI in the matter, ES/EN	Regional systems; accounting lives elsewhere

If you take one thing away

Start with the criterion that eliminates options fastest, not the one that excites you most. If you litigate in Catalonia or Aragón, regional coverage cuts the list to one or two before you look at anything else. If your accountant sits inside the firm, integrated accounting does the same. If you serve clients in English, real bilingualism cuts it from the other side.

And be wary of any comparison — this one included — that tells you one product wins at everything. In this market, that has never once been true.