C2143: Syntax Error Missing ‘;’ Before ‘Type’ in Unreal Engine 5 (UE5 C++) – What It Means & How to Fix It

---

🧠 Why You’re Seeing This Error

The C2143 error happens when the compiler is expecting a ; (semicolon) but instead runs into a type keyword (like int, float, UCLASS, FVector, etc.).

In Unreal Engine 5, this error is often caused by:

• Forgetting to end a class or struct declaration with a semicolon.
• Using Unreal macros like UCLASS() or USTRUCT() incorrectly.
• Misplacing curly braces or preprocessor directives (#if, #endif, etc.).
• Declaring a variable or function in a header file after a broken statement.

This is a syntax error, not a logic error — the code simply isn’t structured correctly for the compiler to understand.

---

💥 Example Error Message

error C2143: syntax error : missing ';' before 'type'

---

🛠️ Example Code

// MyActor.h

USTRUCT()
struct FMyData  // ❌ C2143 error
{
    int32 Score;
    FString Name;
}

What’s wrong?

• We’re missing a ; after the closing } of the struct definition.

---

✅ How to Fix C2143 UE5 – Step-by-Step

---

✔️ 1. Add the Semicolon After Struct or Class Definitions

Fix:

USTRUCT()
struct FMyData
{
    int32 Score;
    FString Name;
}; // ✅ This semicolon ends the declaration properly

---

✔️ 2. Check for Macros Like UCLASS, USTRUCT, UENUM

These Unreal macros must:

• Be placed right before the type definition
• Be followed by a properly declared class/struct
• Not include extra characters or spacing issues

Wrong:

UCLASS
class AMyActor : public AActor  // ❌ missing parentheses in UCLASS()
{
    GENERATED_BODY()
};

Correct:

UCLASS()
class AMyActor : public AActor  // ✅ fixed
{
    GENERATED_BODY()
};

---

✔️ 3. Check for Missing or Misplaced Braces/Preprocessor Tags

Wrong:

#if WITH_EDITOR
void EditorOnlyFunc()
// Forgot #endif or function body...
int32 Health; // ❌ C2143: the compiler’s confused here

Correct:

#if WITH_EDITOR
void EditorOnlyFunc()
{
    // function code
}
#endif

int32 Health;

---

🔍 Bonus Tips

• If you’re editing a header file, make sure all class/struct/function blocks are properly closed before declaring new types.
• Use Visual Studio’s “Format Document” (Ctrl+K, Ctrl+D) to visually spot formatting issues.
• If the error doesn’t make sense, look several lines above the line the compiler says. C2143 often triggers on the next type after the actual mistake.

---

✅ Summary: How to Fix C2143 in UE5

Step	What to Check
Semicolon after class/struct	Add ; after } in UCLASS, USTRUCT
Macro correctness	Use correct syntax for UCLASS(), etc.
Preprocessor blocks	Check #if, #endif, and #include usage
Visual Studio warnings	Use red underlines to find early mistakes