It depends entirely on how you invest. For savings plan investors, Scalable Capital is cheaper — savings plan executions are free on both FREE and PRIME+, with a spread surcharge on crypto ETPs the only exception. IBKR charges a minimum of €3 per trade on Fixed pricing in Germany, so 12 monthly contributions cost around €36 per year, though a contribution that buys a fractional quantity carries a lower €1.25 Fixed minimum. On one-off trades the picture changed on 1 September 2026: Scalable charges a flat €1.99 per trade on Xetra and gettex, on both plans, so FREE and PRIME+ no longer differ on per-order cost. For investors who need multi-currency accounts or USD-denominated assets, IBKR’s institutional FX rates become the more relevant differentiator — Scalable Capital offers no multi-currency account and no USD cash balance.

Scalable Capital is available in Germany, Austria, France, Italy, Spain, and the Netherlands. The robo-advisor, Scalable Wealth, is available to German and Austrian clients only. Automatic Abgeltungsteuer withholding applies to German tax residents. In France, Italy, Spain, and the Netherlands only the self-directed broker is offered: Scalable does not withhold local tax at source in those markets, though its client documents contemplate a free annual report of tax-relevant investment income for non-German tax residents. IBKR is available pan-European and globally with no meaningful feature restrictions by country of residence.

Scalable Capital has the cheaper savings plan offer. It covers 2,700+ ETFs with executions free on both FREE and PRIME+ plans, from €1, on nine execution dates per month, and plans can also be set on shares, funds and crypto ETPs — crypto ETP executions carry a 0.99% or 0.69% spread surcharge depending on plan. Only one savings plan can be set per security. IBKR’s Recurring Investments feature allows scheduled purchases of eligible European-listed shares, but normal Fixed or Tiered commissions still apply per execution — around €3 per contribution on Fixed pricing in Germany, or €1.25 where the contribution buys a fractional quantity. For zero-commission automated ETF investing, Scalable Capital is the cheaper option for investors based in its available markets.

Scalable Capital pays more in most scenarios, but only on cash you actively move into its Overnight account. That account pays 2.50% p.a. on unlimited cash with no minimum balance, on both FREE and PRIME+; cash left sitting in the Scalable broker clearing balance earns 0%. IBKR pays 1.697% p.a. on EUR (rate checked August 2026) on cash above €10,000 only, and accounts with a net asset value below USD 100,000 receive a proportionally reduced rate. On a €15,000 balance, Scalable pays interest on the full €15,000 once it is in the Overnight account, while IBKR pays on €5,000 and scales that down for a small account. Both rates are variable — check each broker’s current figures before relying on them.

Yes, for German tax residents. Without a Freistellungsauftrag, Scalable Capital withholds 25% Kapitalertragsteuer plus the 5.5% solidarity surcharge and, where applicable, church tax, and remits it to the Finanzamt on your behalf. German investors do not need to report broker gains manually in most standard cases. You can submit a Freistellungsauftrag up to the €1,000 individual allowance, or €2,000 for married couples and registered partners, through the platform; one order applies across all your Scalable business relationships. An annual Jahressteuerbescheinigung is issued where tax-relevant transactions occurred, normally delivered to your customer mailbox by the end of April of the following year. IBKR provides an annual activity report but handles no tax obligations on your behalf — you are fully responsible for declaring capital gains and any other local tax obligations.

The two use different frameworks. Scalable Capital Bank GmbH holds a banking permission granted by BaFin and is supervised by BaFin and the Deutsche Bundesbank, so cash sits under deposit-guarantee rules. Scalable states that with PRIME+ cash is distributed across up to five banks, giving up to five times the €100,000 statutory guarantee plus additional voluntary guarantees from participating banks; without PRIME+ it is distributed across banks carrying the €100,000 statutory guarantee per bank, or qualifying UCITS money market funds — each of which is also possible as the sole safekeeping method. IBKR is an investment firm, not a bank. EU client assets are held via Interactive Brokers Ireland Limited, segregated in accounts designated for the exclusive benefit of clients and reconciled daily, with client funds pooled across a range of banks inside and outside the EEA to reduce concentration risk. The Irish Investor Compensation Scheme covers private individuals for 90% of the amount lost, capped at €20,000, and covers failure of the firm rather than market losses.

Yes. IBKR is available to German residents with no feature restrictions. German clients are onboarded to Interactive Brokers Ireland Limited, regulated by the Central Bank of Ireland, with Irish Investor Compensation Scheme cover for private individuals at 90% of the amount lost up to €20,000. All IBKR features are available — multi-currency accounts, global exchange access, the FX conversion workflow, the Stock Yield Enhancement Program, and Recurring Investments. German investors who use IBKR must handle their own Abgeltungsteuer declarations, unlike Scalable Capital which withholds at source for German tax residents.

For German investors doing monthly savings plan contributions into EUR-denominated UCITS ETFs, Scalable Capital wins on total annual cost, convenience, and tax handling — savings plan executions are free, the Overnight account pays 2.50% p.a. with no balance threshold once cash is moved into it, and Abgeltungsteuer is withheld at source. Note that from 1 September 2026 Scalable charges a flat €1.99 on one-off trades at Xetra and gettex on both plans, so lump-sum buying is no longer free on either plan. IBKR becomes the better choice when your portfolio grows in complexity: when you need multi-currency accounts, USD-denominated positions, or global exchange access. The practical path many investors follow is Scalable Capital as the starting point for systematic savings, with IBKR added later as portfolio size and strategy complexity make its advantages material.