Social Security
See your SS contribution before the bill arrives
Monthly Segurança Social contributions are based on your previous quarter's income. That lag catches people off guard - a strong quarter means higher payments three months later. Descodify calculates yours from your actual invoices so the number is never a surprise.
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Calculations free · Guided submissions on Completo. See pricing
How Social Security contributions work
The rate
21.4% of your relevant income. For services, 70% of your gross income is the reference. Effective rate on services revenue:21.4% × 70% = 14.98%.
The quarter lag
You declare income quarterly. That declaration determines your monthly contributions for the next quarter. Invoice €10,000 in Q1? Your Q2 monthly payments reflect that. This means good quarters are followed by higher contribution months - and people who don't track this get caught off guard.
Your first year
New trabalhadores independentes opening their first activity are placed in the regime straight away, but contributions do not start until the first day of the 12th month after the activity start date. It is a deferred start rather than an exemption, and it does not repeat if you reopen activity later. Descodify tracks the date and shows when it lands - so your first contribution doesn't arrive unexpectedly.
The 15% connection
Social Security contributions count toward the 15% expense proof requirement. At most income levels, Social Security contributions alone cover a significant chunk of the threshold. Descodify tracks both together so you see the full picture.
The math, explained
How it's calculated
Portugal uses a 21.4% contribution rate for sole traders. But it's not applied to your full income. For service providers, 70% of your declared quarterly income is used as the reference. For goods sellers, it's 20%. Then there's a monthly cap based on the IAS (Indexante dos Apoios Sociais), currently €537.13 (2026)/month.
The Social Security quarterly declaration (Declaração Trimestral) you submit in January, for example, is based on your income from October through December. The resulting monthly contribution applies to February, March, and April. That quarter-lag is what surprises people.
Descodify calculates all of this from your actual invoices. On your dashboard, you see your estimated monthly contribution before Segurança Social sends the bill. If your contributions have not started yet, Descodify shows that too.
What Descodify shows you
Your dashboard shows your estimated monthly SS contribution based on the invoices you've issued. As you invoice, the number updates. Before each Social Security declaration is due, you see exactly what to declare and what your next three months of payments will be.
Before your contributions start, Descodify shows a countdown to the date. If you have simultaneous employment, it flags that your situation may qualify for reduced contributions.
See the full SS rates and rules reference.
~5 minutes per quarter
Descodify calculates your SS from your invoices. You declare on Segurança Social Direta and check it off.
Invoicing, coming soon
Get early access - free tier includes unlimited invoicing.