Here is the full list of all 91 My Time At Portia achievements. It takes around 200 hours to unlock all of the achievements on Windows.
Accept the proposal from Mint.
Enjoy some fireworks with Dr. Xu.
Complete Phyllis's Dream
Accept Gust's proposal.
You were at fault...
Throw ten parties.
Complete the adventure in the cave with Arlo.
Complete all five Dee-dee transport commissions.
Clear Level 100 of the Deepest Ruins.
Used all items from the Vending Machine in the Deepest Ruins.
Try lasso roping for 50 times.
Expand the land area of the workshop to the maximum.
Getting divorced.
Get more than 40 Ghost Badges in Haunted Cave Exploration.
Play the seesaw and get your playmate to catch a bird.
Get 300 items by kicking trees.
Recognize 5 different constellations.
Win 20 games of Rock Paper Scissors in 3-0 fashion.
Defeated all the people that can spar in Portia.
Give out a gift that the other person doesn't like.
Use 50 Fireworks in one setting.
Accumulated 10 times in the Swing mini-game where the play date is happy with the result.
Get to Level 50 of the Deepest Ruins without using Vending Machines.
Complete the main storyline.
Clear Level 50 of the Deepest Ruins.
Have or adopt a second child.
Unlock all backpack slots.
Place 5 advertisements in the Portia Times for the workshop.
Clear Level 10 of the Deepest Ruins.
Achieve the relationship "Happy Child" with your kid.
Defeat 30 rare monsters.
You missed a date.
Accumulatively give out 500 gifts.
Enter the Deepest Ruins.
Meet Pa.
Have or adopt a child.
Accumulated 10 times during the Doodles mini-game where the play date is happy with the result.
Complete 150 Commerce Guild commissions.
Successfully make 30 different dishes.
Defeat the rogue knight and All Source.
Getting caught by the Sky Shark Pirates.
Have maximum Stamina reach 600.
Throw a party.
Accumulated 10 meals during dates and play dates.
Recover 15 different types of relics.
Have maximum HP reach 2000.
Gather 50 assembly diagrams.
Encounter the rogue knight.
Complete the new Portia Harbor.
Achieve the best relationship with your spouse.
Workshop reputation reaches Level S.
Cumulatively picked up 500 feces.
Find more than 10 Ghost Badges in a single Day of Memories event.
Congratulations!
Complete South Block.
Adopt Scraps.
Everyone likes you!
Accumulatively give out 50 gifts that people like.
Completed 100 Inspections at the Commerce Guild.
Provide 100 Data Discs to the Church of the Light.
Place first in five fishing competitions.
Be ranked number one in a seasonal workshop ranking.
Find a diamond.
Opening Of The Museum
Keep the spiciness of the hotpot above 85 for 10 seconds during the Winter Solstice festival.
Help build the Portia Bridge.
Clear all the levels in any Hazardous Ruins.
Help fix Ack the living AI.
Finish with a over 90% accuracy rate in the Balloons mini-game.
Help the Portia Tree Farm be operational again.
Provide 100 Data Discs to the Research Center.
Open 50 treasure chests.
Discover a mysterious room in Abandoned Ruins.
Talk with other town folks over 500 times.
Gain 150 points in the Dart game.
Adopt Pinky.
Fail at cooking 1 time.
Accumulate 10,000 Gols.
Cut down 200 trees.
Did I just use the Blender to mix feces...?
The first photo taken with someone else.
Pick up 7 gifts during the Day of the Bright Sun event.
Pass the test to enter the Collapsed Wasteland.
Forced to sleep at 3:00 in the morning.
Enter the Abandoned Ruins for the first time.
Register your workshop.
Arrive at Portia.
Win at Cross Five 50 times.
Win the highest possible award in the Slots mini-game.
Pass the trials set by Ginger's family.
Propose to Emily in front of the Pumpkin Princess House.