diff --git a/src-tauri/src/services/accounts/category/dto.rs b/src-tauri/src/services/accounts/category/dto.rs
new file mode 100644
index 0000000..fcacd62
--- /dev/null
+++ b/src-tauri/src/services/accounts/category/dto.rs
@@ -0,0 +1,141 @@
+use sea_orm::ActiveValue::Set;
+use serde::{Deserialize, Serialize};
+
+use crate::db::{
+    DbServiceError,
+    entities::account_category::{
+        ActiveModel as AccountCategoryActiveModel, Model as AccountCategoryModel,
+    },
+};
+use thiserror::Error;
+
+#[derive(Error, Debug)]
+pub enum AccountCategoryServiceError {
+    #[error("database error: {0}")]
+    DbErr(#[from] DbServiceError),
+    #[error("Target not found: {0}")]
+    TargetNotFound(String),
+    #[error("Validation error: {0}")]
+    Validation(String),
+    #[error("unknown error: {0}")]
+    Unknown(String),
+}
+
+impl From<sea_orm::DbErr> for AccountCategoryServiceError {
+    fn from(err: sea_orm::DbErr) -> Self {
+        AccountCategoryServiceError::DbErr(DbServiceError::from(err))
+    }
+}
+
+pub struct AccountCategory {
+    pub id: i64,
+    pub name: String,
+    pub account_type: AccountType,
+    //
+    pub created_at: String,
+    pub updated_at: String,
+}
+
+impl From<AccountCategoryModel> for AccountCategory {
+    fn from(model: AccountCategoryModel) -> Self {
+        Self {
+            id: model.id,
+            name: model.name,
+            account_type: AccountType::from(model.account_type),
+            created_at: model.created_at,
+            updated_at: model.updated_at,
+        }
+    }
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub enum AccountType {
+    #[serde(rename = "Asset")]
+    Asset, // Positive balance, e.g. Checking, Savings
+    #[serde(rename = "Liability")]
+    Liability, // Negative balance, e.g. Credit Card
+    #[serde(other, rename = "Unknown")]
+    Unknown, // Fallback for unknown types
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct CreateAccountCategoryRequest {
+    pub name: String,
+    pub account_type: AccountType,
+}
+
+impl CreateAccountCategoryRequest {
+    pub fn validate(&self) -> Result<(), AccountCategoryServiceError> {
+        if self.name.trim().is_empty() {
+            return Err(AccountCategoryServiceError::Validation(
+                "Name cannot be empty".to_string(),
+            ));
+        }
+        if let AccountType::Unknown = self.account_type {
+            return Err(AccountCategoryServiceError::Validation(
+                "Invalid account type".to_string(),
+            ));
+        }
+        Ok(())
+    }
+}
+
+impl From<CreateAccountCategoryRequest> for AccountCategoryActiveModel {
+    fn from(request: CreateAccountCategoryRequest) -> Self {
+        AccountCategoryActiveModel {
+            name: Set(request.name),
+            account_type: Set(request.account_type.to_string()),
+            created_at: Set(chrono::Utc::now().to_rfc3339()),
+            updated_at: Set(chrono::Utc::now().to_rfc3339()),
+            ..Default::default()
+        }
+    }
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct UpdateAccountCategoryRequest {
+    pub name: Option<String>,
+    pub account_type: Option<AccountType>,
+}
+
+impl UpdateAccountCategoryRequest {
+    pub fn validate(&self) -> Result<(), AccountCategoryServiceError> {
+        if let Some(name) = &self.name {
+            if name.trim().is_empty() {
+                return Err(AccountCategoryServiceError::Validation(
+                    "Name cannot be empty".to_string(),
+                ));
+            }
+        }
+        Ok(())
+    }
+
+    pub fn apply_to(self, transaction: &mut AccountCategoryActiveModel) {
+        if let Some(name) = self.name {
+            transaction.name = Set(name);
+        }
+        if let Some(account_type) = self.account_type {
+            transaction.account_type = Set(account_type.to_string());
+        }
+    }
+}
+
+impl From<String> for AccountType {
+    fn from(s: String) -> Self {
+        match s.as_str() {
+            "Asset" => AccountType::Asset,
+            "Liability" => AccountType::Liability,
+            _ => AccountType::Unknown,
+        }
+    }
+}
+
+impl std::fmt::Display for AccountType {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            AccountType::Asset => write!(f, "Asset"),
+            AccountType::Liability => write!(f, "Liability"),
+            AccountType::Unknown => write!(f, "Unknown"),
+        }
+    }
+}
diff --git a/src-tauri/src/services/accounts/category/mod.rs b/src-tauri/src/services/accounts/category/mod.rs
new file mode 100644
index 0000000..73dad09
--- /dev/null
+++ b/src-tauri/src/services/accounts/category/mod.rs
@@ -0,0 +1,6 @@
+mod dto;
+mod repo;
+mod service;
+
+pub use dto::*;
+pub use service::*;
diff --git a/src-tauri/src/services/accounts/category/repo.rs b/src-tauri/src/services/accounts/category/repo.rs
new file mode 100644
index 0000000..6407592
--- /dev/null
+++ b/src-tauri/src/services/accounts/category/repo.rs
@@ -0,0 +1,151 @@
+use crate::{
+    db::{
+        Db,
+        entities::account_category::{
+            ActiveModel as AccountCategoryActiveModel, Entity as AccountCategoryEntity,
+        },
+    },
+    services::accounts::category::dto::{
+        AccountCategory, AccountCategoryServiceError, CreateAccountCategoryRequest,
+        UpdateAccountCategoryRequest,
+    },
+};
+use migration::OnConflict;
+use sea_orm::{
+    ActiveModelTrait, ActiveValue::Set, ColumnTrait, DatabaseConnection, EntityTrait,
+    IntoActiveModel, ModelTrait, PaginatorTrait, QueryFilter,
+};
+
+#[async_trait::async_trait]
+pub trait AccountCategoryRepoService: Send + Sync + 'static {
+    async fn get_categories(&self) -> Result<Vec<AccountCategory>, AccountCategoryServiceError>;
+    async fn create_category(
+        &self,
+        create_request: CreateAccountCategoryRequest,
+    ) -> Result<i64, AccountCategoryServiceError>;
+
+    async fn create_category_with_tx(
+        &self,
+        create_request: CreateAccountCategoryRequest,
+        tx: &Db,
+    ) -> Result<i64, AccountCategoryServiceError>;
+
+    async fn update_category(
+        &self,
+        id: &i64,
+        update_request: UpdateAccountCategoryRequest,
+    ) -> Result<(), AccountCategoryServiceError>;
+
+    async fn update_category_with_tx(
+        &self,
+        id: &i64,
+        update_request: UpdateAccountCategoryRequest,
+        tx: &Db,
+    ) -> Result<(), AccountCategoryServiceError>;
+
+    async fn delete_category(&self, id: &i64) -> Result<(), AccountCategoryServiceError>;
+}
+
+pub struct AccountCategoryRepoServiceImpl {
+    db: DatabaseConnection,
+}
+
+impl AccountCategoryRepoServiceImpl {
+    pub fn new(db: DatabaseConnection) -> Self {
+        Self { db }
+    }
+}
+
+#[async_trait::async_trait]
+impl AccountCategoryRepoService for AccountCategoryRepoServiceImpl {
+    async fn get_categories(&self) -> Result<Vec<AccountCategory>, AccountCategoryServiceError> {
+        let categories = AccountCategoryEntity::find().all(&self.db).await?;
+        Ok(categories.into_iter().map(|model| model.into()).collect())
+    }
+
+    async fn create_category(
+        &self,
+        create_request: CreateAccountCategoryRequest,
+    ) -> Result<i64, AccountCategoryServiceError> {
+        self.create_category_with_tx(create_request, &(&self.db).into())
+            .await
+    }
+
+    async fn create_category_with_tx(
+        &self,
+        create_request: CreateAccountCategoryRequest,
+        tx: &Db,
+    ) -> Result<i64, AccountCategoryServiceError> {
+        create_request.validate()?;
+        let new_category: AccountCategoryActiveModel = create_request.into();
+
+        let res = AccountCategoryEntity::insert(new_category)
+            .on_conflict(
+                // force update to ensure a record is returned
+                OnConflict::column(crate::db::entities::account_category::Column::Name)
+                    .update_column(crate::db::entities::account_category::Column::Name)
+                    .to_owned(),
+            )
+            .exec_with_returning(tx)
+            .await?;
+        Ok(res.id)
+    }
+
+    async fn delete_category(&self, id: &i64) -> Result<(), AccountCategoryServiceError> {
+        // check if any accounts are using this category before deleting
+        let accounts_using_category = crate::db::entities::account::Entity::find()
+            .filter(crate::db::entities::account::Column::AccountCategoryId.eq(*id))
+            .count(&self.db)
+            .await?;
+
+        if accounts_using_category > 0 {
+            return Err(AccountCategoryServiceError::Validation(
+                "Cannot delete category that has accounts".to_string(),
+            ));
+        }
+
+        let category = AccountCategoryEntity::find_by_id(*id).one(&self.db).await?;
+        if let Some(category) = category {
+            category.delete(&self.db).await?;
+            Ok(())
+        } else {
+            Err(AccountCategoryServiceError::TargetNotFound(
+                "Category not found".to_string(),
+            ))
+        }
+    }
+
+    async fn update_category(
+        &self,
+        id: &i64,
+        update_request: UpdateAccountCategoryRequest,
+    ) -> Result<(), AccountCategoryServiceError> {
+        self.update_category_with_tx(id, update_request, &(&self.db).into())
+            .await
+    }
+
+    async fn update_category_with_tx(
+        &self,
+        id: &i64,
+        update_request: UpdateAccountCategoryRequest,
+        tx: &Db,
+    ) -> Result<(), AccountCategoryServiceError> {
+        update_request.validate()?;
+
+        let category = AccountCategoryEntity::find_by_id(*id)
+            .one(&self.db)
+            .await
+            .map(|opt| opt.map(|model| model.into_active_model()))?;
+
+        if let Some(mut category) = category {
+            update_request.apply_to(&mut category);
+            category.updated_at = Set(chrono::Utc::now().to_rfc3339());
+            category.update(tx).await?;
+            Ok(())
+        } else {
+            Err(AccountCategoryServiceError::TargetNotFound(
+                "Category not found".to_string(),
+            ))
+        }
+    }
+}
diff --git a/src-tauri/src/services/accounts/category/service.rs b/src-tauri/src/services/accounts/category/service.rs
new file mode 100644
index 0000000..b6e9e89
--- /dev/null
+++ b/src-tauri/src/services/accounts/category/service.rs
@@ -0,0 +1,107 @@
+use std::sync::Arc;
+
+use crate::{
+    db::Db,
+    services::accounts::category::{
+        dto::{
+            AccountCategory, AccountCategoryServiceError, CreateAccountCategoryRequest,
+            UpdateAccountCategoryRequest,
+        },
+        repo::AccountCategoryRepoService,
+    },
+};
+use sea_orm::DatabaseConnection;
+
+#[async_trait::async_trait]
+pub trait AccountCategoryService: Send + Sync + 'static {
+    async fn get_categories(&self) -> Result<Vec<AccountCategory>, AccountCategoryServiceError>;
+    async fn create_category(
+        &self,
+        create_request: CreateAccountCategoryRequest,
+    ) -> Result<i64, AccountCategoryServiceError>;
+
+    async fn create_category_with_tx(
+        &self,
+        create_request: CreateAccountCategoryRequest,
+        tx: &Db,
+    ) -> Result<i64, AccountCategoryServiceError>;
+
+    async fn update_category(
+        &self,
+        id: &i64,
+        update_request: UpdateAccountCategoryRequest,
+    ) -> Result<(), AccountCategoryServiceError>;
+
+    async fn update_category_with_tx(
+        &self,
+        id: &i64,
+        update_request: UpdateAccountCategoryRequest,
+        tx: &Db,
+    ) -> Result<(), AccountCategoryServiceError>;
+
+    async fn delete_category(&self, id: &i64) -> Result<(), AccountCategoryServiceError>;
+}
+
+pub struct AccountCategoryServiceImpl<T>
+where
+    T: super::repo::AccountCategoryRepoService + ?Sized,
+{
+    db: DatabaseConnection,
+    repo: Arc<T>,
+}
+
+impl AccountCategoryServiceImpl<super::repo::AccountCategoryRepoServiceImpl> {
+    pub fn new(db: DatabaseConnection) -> Self {
+        Self {
+            db: db.clone(),
+            repo: Arc::new(super::repo::AccountCategoryRepoServiceImpl::new(db.clone())),
+        }
+    }
+}
+
+#[async_trait::async_trait]
+impl AccountCategoryService
+    for AccountCategoryServiceImpl<super::repo::AccountCategoryRepoServiceImpl>
+{
+    async fn get_categories(&self) -> Result<Vec<AccountCategory>, AccountCategoryServiceError> {
+        self.repo.get_categories().await
+    }
+
+    async fn create_category(
+        &self,
+        create_request: CreateAccountCategoryRequest,
+    ) -> Result<i64, AccountCategoryServiceError> {
+        self.repo.create_category(create_request).await
+    }
+
+    async fn create_category_with_tx(
+        &self,
+        create_request: CreateAccountCategoryRequest,
+        tx: &Db,
+    ) -> Result<i64, AccountCategoryServiceError> {
+        self.repo.create_category_with_tx(create_request, tx).await
+    }
+
+    async fn delete_category(&self, id: &i64) -> Result<(), AccountCategoryServiceError> {
+        self.repo.delete_category(id).await
+    }
+
+    async fn update_category(
+        &self,
+        id: &i64,
+        update_request: UpdateAccountCategoryRequest,
+    ) -> Result<(), AccountCategoryServiceError> {
+        self.repo.update_category(id, update_request).await
+    }
+
+    async fn update_category_with_tx(
+        &self,
+        id: &i64,
+        update_request: UpdateAccountCategoryRequest,
+        tx: &Db,
+    ) -> Result<(), AccountCategoryServiceError> {
+        self.repo
+            .update_category_with_tx(id, update_request, tx)
+            .await
+    }
+}