The Address Book is the place where you can save your withdrawal addresses for all supported crypto assets on the Nexo platform. This option would save you time and add additional security as you would not have to re-enter the same address every time. The number of addresses you can keep a record of is unlimited. Both personal wallets or wallets of exchanges can be added to your Address Book.
It is important to note that saved addresses are not whitelisted unless Whitelisting is enabled.
Whitelisting is a security feature that limits withdrawals to only the addresses you have added to your Address Book. Upon enabling it you will be required to set up your Extra Security option. This is a feature that allows you to select the length of the security delay for adding new addresses or disabling Whitelisting altogether. You can choose between the three pre-set options - 'None', '24h', '72h', or you can enter a 'Custom' timeframe that best suits your needs. It can be as low as 5 hours or as much as 10,000 hours.
Once Whitelisting is activated you have a 4-hour cool-off window to add new addresses instantly or disable the whitelisting. After this period ends, you have to wait for the pre-set Extra Security time to pass before any changes you make come into effect.
Important notice: The Whitelisting option applies to the whole portfolio and all of the supported crypto assets. If it is turned ON, you will be able to withdraw only to the addresses from your Address Book. You will NOT be able to withdraw assets for which you have not added a withdrawal address in the Address Book. Please make sure you do so before enabling Whitelisting or within the 4-hour cool-off period. In case you have not done this, you can still whitelist an address, but you will be required to disable the Whitelisting and wait for the Extra Security timeframe to pass (if you have set an Extra Security Level other than 'None').
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