Full list of all 33 Island Saver achievements worth 2,000 gamerscore. It takes around 6-8 hours to unlock all of the achievements in the base game on Xbox One.
The base game contains 13 achievements worth 1,000 Gamerscore, and there are 2 DLC packs containing 20 achievements worth 1,000 Gamerscore.
Complete charity mission and send Litterbugs home
Exchange all 5 currencies into doubloons at least once
Repay a bank loan
Exchange any currency at its best price
Deposit 1000 gold doubloons
Take out a bank loan
Barter with Kiwi
Use tax to build a bridge
Spend 100 in Pigby's Store
Earn 50 Tax Tokens
Earn first interest on your savings
Deposit 100 gold doubloons
Use tax to empty recycler
Collect a piece of broken Exit Bot
Find all Newton's lost fossils
Build tax bridge
Help Newton repay all his debts
Feed a flying Pteranodon
Insert battery into Giant Tax Bot
Ride on an Ankylosaurus
Ride on a Velociraptor
Use T-Rex to smash amber
Open the Electric Gate
Plant a giant beanstalk
Find all the Golden Goose eggs
Award all fruit supply contracts
Find Truffles's lost dog
Paint both billboards on Oasis Island
Build portal pipe on Hub Island
Glide on a dragon
Use a magic portal
Smash a wooden crate
Help smoothie stall re-open for business