LifeSim
Play

Updated October 25, 2026

How to become a mermaid in The Sims 4

How to become a mermaid in The Sims 4 with Island Living: Create a Sim, the kelp method, powers, hydration, cheats, babies, and the cure.

Lifesim, Inc.

What pack has mermaids in The Sims 4?

The Island Living expansion pack adds mermaids. You need this pack to make a mermaid or to become one. The base game has no mermaids.

Sims Community says that the pack came out for PC and Mac on June 21, 2019. Vulcan Post gives July 16 for PlayStation 4 and Xbox One. The pack adds the island world of Sulani. The EA page lists 182 Build Mode items and 136 Create a Sim items.

We checked this guide against fan guides and the EA store page on October 25, 2026. The Sims Wiki did not load for us, so we did not use it. Updates can change small details in your game.

For the other packs, read our list of Sims 4 packs.

How do you become a mermaid in The Sims 4?

Make a new mermaid in Create a Sim, or feed Mermadic Kelp to a Sim that you already have. A cheat also works. A child can also be born a mermaid.

How to make a mermaid in Create a Sim

Open Create a Sim and add a new Sim. Choose the occult option, then choose the mermaid. Sims Community says that you cannot change a Sim that already exists into a mermaid in Create a Sim.

You can pick fin styles and fin colors. Some swatches have patterns or shine. You can also choose glowing eyes. Sims Community says that you can unlink the human form and the mermaid form, so a change to one does not change the other.

How to turn an existing Sim into a mermaid with kelp

  1. Get one Mermadic Kelp. The next section shows where.
  2. Have the Sim eat the kelp. The Sim gets a moodlet that lasts 24 hours.
  3. Send the Sim into the water before the moodlet ends. Swim or dive.
  4. Look at the plumbob. GameRevolution says that a ring around it shows a mermaid.

Sims Community calls the moodlet “Strange Sensations.” If the moodlet ends first, Snooty Sims says that you need a new kelp. Then you start again.

What is a merwoke household?

GameRevolution and Gameranx say that mermaids are only available to a “merwoke” household. GameRevolution says that this is a household that has had mermaid experience. Gameranx says that a merwoke toggle can turn mermaids off.

Where do you find Mermadic Kelp in The Sims 4?

Buy it in the Rewards Store for 500 Satisfaction Points. This is the fastest way. The other ways are random and happen in Sulani.

WhereHow
Rewards StorePay 500 Satisfaction Points
Mua Pel’am caveExplore the Underground Pools near the waterfall
The sea in SulaniFish, or dive for treasure
The beach in SulaniDig through the sand
Deep water buoysDive around them
Mermaids and dolphinsTalk to mermaids, or play fetch with a dolphin friend

Snooty Sims says that the cave gives a small chance to find 10 pieces at once. You need two pieces to turn back later, so keep the spare kelp.

Do you need more points? Read the Satisfaction Points cheat.

What can mermaids do in The Sims 4?

Mermaids sing songs that change the moods of other Sims. They also call dolphins, attract fish, and change the weather. Most powers cost Hydration.

PowerHydration costWhat it does
Siren’s Lullaby30Four songs. Each gives a mood: Tense, Flirty, Inspired, or Sad.
Mermaid’s Kiss30Kiss a Sim without a romantic relationship. It is stronger in water.
Siren’s Call100In water only. Pulls a Sim under the water and drains its needs.
Summon Ocean Threat30In water only. The target Sim panics in the water.
Call Over Azure Dolphin30In water only. Calls a dolphin, which becomes a soulmate at once.
Aquatic Lure30At a fishing spot or on a boat. Attracts more fish and rarer fish.
Call Clear Skies, Rainstorm, Thunderstorm75 eachChanges the weather. Needs the Seasons expansion pack.

The costs come from Sims Community. Each power also has a cooldown. A power with a higher cost has a longer cooldown.

What does Siren’s Call do to the mermaid?

It fills the needs of the mermaid. TheGamer and Gameranx say that the mermaid gets +100 to its needs. The target Sim gets an Uncomfortable moodlet. Sims Community says that the target can drown if it does not reach the shore in time.

Do good and evil mermaids have different powers?

Yes. Sims Community says that a mermaid with the Good trait cannot use Siren’s Call, Summon Ocean Threat, or Call Thunderstorm. A mermaid with the Evil trait cannot use Call Clear Skies. A mermaid with neither trait can use all the powers.

What can mermaids do without Hydration?

  • Swim faster than a Sim with level 10 Fitness. TheGamer gives this fact.
  • Sleep in the water without a bed.
  • Free dive before they reach Fitness level 3.
  • Change into the mermaid form in a bath or a swimming pool.
  • Talk to the fish in an aquarium.

How does Hydration work for Sims 4 mermaids?

Hydration replaces the Hygiene need. It goes down slowly when the mermaid is out of the water. Put the mermaid in water to fill it again.

Hydration is also the power source. A mermaid with low Hydration cannot use its powers. Sims Community says that powers on land use up Hydration faster. In the water, Hydration is almost unlimited.

How do you fill Hydration?

  • Swim in the sea. This is the fastest way.
  • Swim in a pool.
  • Take a bath or a shower.
  • Drink water. Sims Community lists this way.

TheGamer also lists a sink. We could not confirm the sink in a second source, so use the sea or a bath.

What happens when Hydration is low?

TheGamer says that the mermaid becomes stinky and uncomfortable. It also loses its powers until you fill the need.

What are the weaknesses of mermaids in The Sims 4?

The main weakness is Hydration. A mermaid must go into the water often. The fan guides also list some things that a mermaid cannot do.

  • It cannot snorkel.
  • It cannot scuba dive, and it cannot use or buy scuba gear.
  • It cannot use ladders, such as the ladder of a pier. Swim to shallow water to get out.
  • It cannot change form in a shower.
  • It has no powers on land unless it has Hydration to spend.

Can a mermaid die in The Sims 4?

We found no source that we could open that confirms a death from low Hydration. Do not count on it either way. Kotaku tested the powers on other Sims to see if they kill. The tests were “inconclusive.”

Do mermaids age in The Sims 4?

Yes. Sims Community says that mermaids age at the same speed as human Sims. A mermaid is not immortal like a vampire. Compare it with Sims 4 vampires and Sims 4 werewolves.

How do you stop being a mermaid in The Sims 4?

Have the mermaid eat two Mermadic Kelp, one after the other. The second kelp removes the mermaid life state. Or use the remove cheat in the next section.

  1. Get two Mermadic Kelp.
  2. Have the mermaid eat the first kelp.
  3. Have it eat the second kelp at once.
  4. Send the Sim into the water. TheGamer says that this step completes the change.
  5. Look at the plumbob. GameRevolution says that no ring means a normal Sim.

Does a mermaid get legs on land?

Yes. The mermaid walks on land in its human form. Its tail comes back when it goes into the water again. This is not a cure. To stop being a mermaid, use the two kelp.

What are the Sims 4 mermaid cheats?

Open the cheat console and type testingcheats true. Then type one of the cheats below. On PC, press Control + Shift + C to open the console.

CheatWhat it does
traits.equip_trait trait_OccultMermaidMakes the Sim a mermaid at once
traits.remove_trait trait_OccultMermaidMakes the mermaid a normal Sim again
traits.equip_trait trait_OccultMermaid_MermaidFormGives the mermaid its tail on land
traits.remove_trait trait_OccultMermaid_TYAEChanges Hydration back to Hygiene after the Sim turns normal
traits.equip_trait trait_ChildofTheOceanGives the Child of the Ocean trait
traits.equip_trait trait_FriendOfTheSeaGives the Master of the Sea reward trait

Sims Community and Snooty Sims list the first three cheats. Only Snooty Sims lists the other three. Snooty Sims also suggests the fan mod All Cheats Fix by TwistedMexi.

One reader on Sims Community says that the remove cheat did not work for them. If this happens, use the two kelp. For the full list, read all Sims 4 cheats.

Can mermaids have babies in The Sims 4?

Yes. TheGamer says that a child born into a mermaid family has a chance to be a mermaid. You cannot make a mermaid baby, toddler, or child in Create a Sim.

A mermaid child has the Hydration need but acts like a normal child. It has no tail. It gets its tail and its powers when it becomes a teen.

We could not open a page that gives the exact chance of a mermaid baby. Fan pages quote a number, but we did not confirm it. Read how to have a baby in The Sims 4 for the steps.

Where does LifeSim fit?

It does not fit if you want mermaids. LifeSim has no mermaids, no occult life states, and no packs. For tails, Sulani, and Siren’s Call, play The Sims 4 with Island Living.

LifeSim is a free AI life simulation game in your browser. You live one slow life on a real map of Earth. You write what you do in your own words. The people around you talk back and remember what you did.

Read LifeSim vs The Sims for the full comparison.

Questions

Is Island Living the only Sims 4 pack with mermaids?

All the sources that we read name Island Living as the mermaid pack. None of them names another pack.

How much is Mermadic Kelp in the Rewards Store?

It costs 500 Satisfaction Points. Every guide that we read gives the same price.

How long do you have to get in the water after you eat the kelp?

You have 24 game hours. After that, the moodlet ends and you need a new kelp.

Can a child become a mermaid in The Sims 4?

A child can be a mermaid from birth. It shows no tail and no powers until it becomes a teen.

Can a mermaid use a swimming pool?

Yes. A mermaid can swim in a pool, and the pool fills its Hydration.

Can Sims become friends with dolphins?

Yes. Vulcan Post says that normal Sims can also befriend dolphins. Only mermaids can call a dolphin for 30 Hydration.

More Sims guides

Sources

New to life sims? Read what a life simulator is.

Keep reading

All posts