What kind of info will they share directly from DEGIRO and IB?Degiro does share under CRS as they clearly state. IB will also. Any broker that doesn't now will do later. I posted here two brokers here you can use but it will not last long as those countries will join CRS at some point.
FAQ on Taxes | Degiro online broker
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"To help fight tax evasion and to protect the integrity of tax systems, governments around the world introduced a system for automatic exchange of information on financial accounts between countries. This system is known as CRS and is incorporated in Dutch law.
As a result, DEGIRO is obliged to verify in which country a client is (potentially) a tax resident. DEGIRO is obliged to share this information with the Dutch tax authorities. Subsequently, the Dutch tax authorities share this information with the tax authorities in the country where the relevant client (potentially) is a tax resident."
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What kind of info will they share directly from DEGIRO and IB?
Let's say you have no cash balances as of 31st Dec, only stocks.
Will they share the stock quantity or stock valuation at the time?
IB allow indicating tax residency (country from drop-down list) and "residence address"...which one gets reported as per CRS?