How to Add Another Sim in Sims 4: Complete Guide to Expanding Your Household

Whether you're building a bustling family, adding a roommate, or creating a complex social story, knowing how to add another Sim to your household in The Sims 4 is one of the most fundamental skills in the game. There are several distinct methods, and which one applies to you depends on where you are in gameplay, what you're trying to achieve, and whether you're playing with mods or cheats enabled.

Why It Matters How You Add a Sim

Adding a Sim isn't just one action — it's a category of actions. You might want to:

• Add a brand-new Sim you've never created before
• Move an existing NPC or townie into your household
• Merge two separate player households
• Add a baby or child through in-game progression
• Use Create-A-Sim (CAS) to drop in a fully designed Sim from scratch

Each of these uses a different pathway, and mixing them up is one of the most common sources of confusion for newer players.

Method 1: Adding a Sim Through Create-A-Sim

The most direct approach is building a new Sim before your household is ever placed in a lot.

From the main menu:

1. Select Create New Game
2. Enter Create-A-Sim
3. Click the "+" icon (the silhouette with a plus sign) at the bottom of the screen to add additional Sims
4. Customize each Sim, then place the household on a lot

You can add up to 8 Sims per household in the base game. Once you've hit that cap, the option to add more will be greyed out.

From within an active save:

1. Click on a mirror, dresser, or wardrobe in your Sim's home
2. Select "Change Sim" — this opens a limited CAS that lets you edit existing Sims but not add new ones directly this way

To add a new Sim mid-game through CAS, you'll typically need to either use cheats or go through the household management screen.

Method 2: Using the Manage Households Menu 🎮

This is the in-game method most players overlook.

1. Click the "..." (three dots) menu in the top-right corner of the screen
2. Select Manage Worlds
3. From there, open Manage Households
4. Find the household you want to modify and click the pencil/edit icon
5. This reopens CAS, where you can add new Sims using the "+" icon

This method works cleanly without cheats and lets you design a Sim from scratch to join an existing household.

Method 3: Moving an Existing Sim Into Your Household

If there's already a Sim in the world — a townie, a neighbor, or someone your Sim has befriended — you can move them in through social interaction or the household menu.

Via social interaction:

1. Build a strong relationship with the target Sim (typically Friend level or higher, sometimes Romantic Partner or Fiancé depending on context)
2. Click on the Sim and look under Friendly or Romantic interactions
3. Select "Ask to Move In"
4. Confirm the prompt — they'll join your household along with any funds they're carrying

Via Manage Households:

1. Go to Manage Worlds → Manage Households
2. Locate the Sim's household and use the household split/merge tool (the arrows icon) to move individual Sims between households

The merge tool gives you more control and doesn't require a relationship threshold, which is useful when you're managing multiple storylines or households simultaneously.

Method 4: Using Cheats to Add a Sim

For players comfortable with the game's cheat console, there are faster routes.

Enable cheats first:

• PC/Mac: Press Ctrl + Shift + C
• Console: Hold all four triggers simultaneously
• Type testingcheats true and press Enter

Once enabled, you can:

• Shift-click on any Sim in the world and select "Add to Family" to instantly pull them into your active household
• Use bb.enablefreebuild in combination with CAS cheats for more flexibility in controlled environments

The Shift-click "Add to Family" method is particularly fast for players who want to incorporate specific NPCs or pre-made Sims without going through relationship-building.

Method 5: Biological and In-Game Progression

Sims can also grow a household the long way — through pregnancy, adoption, or aging up existing life stages.

• Pregnancy is triggered through the "Try for Baby" interaction and follows a multi-day progression before a new Sim joins the household as an infant or toddler
• Adoption is accessed via a computer: Household → Hire a Service → Adopt a Child (costs in-game Simoleons and involves a wait period)
• Both methods add Sims organically and are subject to the 8-Sim household cap

Variables That Affect Your Approach

Not every method is available in every situation. A few factors shape what's actually possible:

When Results Vary by Playstyle

A player running a legacy household challenge will approach this very differently than someone doing a build-and-design playthrough or a casual sandbox session. Legacy players often care about relationship-based move-ins and keeping the household count intentional. Builders and storytellers may lean heavily on CAS and Manage Households. Players experimenting with NPCs or mods may use cheat-based additions constantly.

The method that fits cleanly into one playstyle can feel disruptive or even cheat-like in another. How you want your Sim's world to feel — organic, controlled, or somewhere between — shapes which approach actually makes sense for your game. 🎯