diff --git a/src/AsteriskAPIManager/api_manager.py b/src/AsteriskAPIManager/api_manager.py
index 121ff4c..bbec570 100644
--- a/src/AsteriskAPIManager/api_manager.py
+++ b/src/AsteriskAPIManager/api_manager.py
@@ -57,6 +57,10 @@ class AsteriskManagerClient:
         response = await self._request('GET', f'/sip/{account_id}')
         return SIPAccount(**response)
 
+    async def update_sip_account(self, account_id: int, data: SIPAccountIn):
+        response = await self._request('PATCH', f'/sip/{account_id}', json=data.model_dump(exclude_unset=True, exclude_none=True))
+        return SIPAccount(**response)
+
     async def set_sip_register_status(self, account_id: int, is_registered: bool):
         data = {"is_registered": is_registered}
         response = await self._request('PATCH', f'/sip/{account_id}', json=data)
diff --git a/src/AsteriskAPIManager/data_models.py b/src/AsteriskAPIManager/data_models.py
index 415f5e9..3dfc824 100644
--- a/src/AsteriskAPIManager/data_models.py
+++ b/src/AsteriskAPIManager/data_models.py
@@ -79,6 +79,54 @@ class SIPAccount(BaseModel):
         extra = "ignore"
         from_attributes = True
 
+class SIPAccountIn(BaseModel):
+    """
+    SIP-аккаунт.
+    """
+    owner_id: Optional[int]
+    name: Optional[str]
+    is_registered: Optional[bool]
+    username: Optional[str]
+    password: Optional[str]
+    
+    server_url: Optional[str]
+    port: Optional[int]
+    internal_number: Optional[str]
+    endpoint_name: Optional[str]
+
+    @validator("username")
+    def validate_username(cls, v):
+        if v and len(v) > 40:
+            raise ValueError("Username too long (max 40 characters)")
+        return v
+
+    @validator("name")
+    def validate_name(cls, v):
+        if v and len(v) > 255:
+            raise ValueError("Name too long (max 255 characters)")
+        return v
+
+    @validator("internal_number")
+    def validate_internal_number(cls, v):
+        if v and len(v) > 255:
+            raise ValueError("Internal number too long (max 255 characters)")
+        return v
+
+    @validator("endpoint_name")
+    def validate_endpoint_name(cls, v):
+        if v and len(v) > 255:
+            raise ValueError("Endpoint name too long (max 255 characters)")
+        return v
+
+    @validator("port")
+    def validate_port(cls, v):
+        if v is not None and not (0 <= v <= 65535):
+            raise ValueError("Port must be between 0 and 65535")
+        return v
+
+    class Config:
+        extra = "ignore"
+        from_attributes = True
 
 
 class AccessResponse(BaseModel):