diff --git a/ga-core/src/main/java/com/ga/core/mapper/installment/InstallmentPlanMapper.java b/ga-core/src/main/java/com/ga/core/mapper/installment/InstallmentPlanMapper.java
new file mode 100644
index 0000000..0e0d1c7
--- /dev/null
+++ b/ga-core/src/main/java/com/ga/core/mapper/installment/InstallmentPlanMapper.java
@@ -0,0 +1,34 @@
+package com.ga.core.mapper.installment;
+
+import com.ga.core.vo.installment.InstallmentPlanResp;
+import com.ga.core.vo.installment.InstallmentPlanSearchParam;
+import com.ga.core.vo.installment.InstallmentPlanVO;
+import org.apache.ibatis.annotations.Mapper;
+import org.apache.ibatis.annotations.Param;
+
+import java.util.List;
+
+@Mapper
+public interface InstallmentPlanMapper {
+
+    List<InstallmentPlanResp> selectList(InstallmentPlanSearchParam param);
+
+    InstallmentPlanResp selectDetailById(@Param("planId") Long planId);
+
+    InstallmentPlanVO selectById(@Param("planId") Long planId);
+
+    /** 계약의 전체 분급 계획 조회 (계약 상세 화면용) */
+    List<InstallmentPlanVO> selectByContract(@Param("contractId") Long contractId);
+
+    /** 정산월의 SCHEDULED 분급 계획 조회 (배치 지급 처리용) */
+    List<InstallmentPlanVO> selectScheduledByMonth(@Param("settleMonth") String settleMonth);
+
+    int insert(InstallmentPlanVO vo);
+
+    /** 7년치 분급 계획 일괄 생성 */
+    int insertBatch(@Param("list") List<InstallmentPlanVO> list);
+
+    int update(InstallmentPlanVO vo);
+
+    int updateStatus(@Param("planId") Long planId, @Param("status") String status);
+}
diff --git a/ga-core/src/main/java/com/ga/core/mapper/installment/InstallmentRatioMapper.java b/ga-core/src/main/java/com/ga/core/mapper/installment/InstallmentRatioMapper.java
new file mode 100644
index 0000000..90e70c9
--- /dev/null
+++ b/ga-core/src/main/java/com/ga/core/mapper/installment/InstallmentRatioMapper.java
@@ -0,0 +1,32 @@
+package com.ga.core.mapper.installment;
+
+import com.ga.core.vo.installment.InstallmentRatioResp;
+import com.ga.core.vo.installment.InstallmentRatioSearchParam;
+import com.ga.core.vo.installment.InstallmentRatioVO;
+import org.apache.ibatis.annotations.Mapper;
+import org.apache.ibatis.annotations.Param;
+
+import java.util.List;
+
+@Mapper
+public interface InstallmentRatioMapper {
+
+    List<InstallmentRatioResp> selectList(InstallmentRatioSearchParam param);
+
+    InstallmentRatioResp selectDetailById(@Param("ratioId") Long ratioId);
+
+    InstallmentRatioVO selectById(@Param("ratioId") Long ratioId);
+
+    /** 특정 날짜에 유효한 분급 비율 1건 (planYear + productCategory 조합) */
+    InstallmentRatioVO selectActive(@Param("productCategory") String productCategory,
+                                    @Param("planYear") Integer planYear,
+                                    @Param("baseDate") String baseDate);
+
+    /** 특정 날짜에 유효한 1~7년 차 전체 비율 조회 (분급 계획 일괄 생성 시 사용) */
+    List<InstallmentRatioVO> selectAllActiveRatios(@Param("productCategory") String productCategory,
+                                                   @Param("baseDate") String baseDate);
+
+    int insert(InstallmentRatioVO vo);
+
+    int update(InstallmentRatioVO vo);
+}
diff --git a/ga-core/src/main/java/com/ga/core/vo/installment/InstallmentPlanResp.java b/ga-core/src/main/java/com/ga/core/vo/installment/InstallmentPlanResp.java
new file mode 100644
index 0000000..b6a2724
--- /dev/null
+++ b/ga-core/src/main/java/com/ga/core/vo/installment/InstallmentPlanResp.java
@@ -0,0 +1,25 @@
+package com.ga.core.vo.installment;
+
+import lombok.Data;
+
+import java.math.BigDecimal;
+import java.time.LocalDateTime;
+
+@Data
+public class InstallmentPlanResp {
+    private Long planId;
+    private Long contractId;
+    private String policyNo;
+    private String productName;
+    private Long agentId;
+    private String agentName;
+    private Integer planYear;
+    private Integer planMonth;
+    private String settleMonth;
+    private BigDecimal expectedAmount;
+    private BigDecimal paidAmount;
+    private LocalDateTime paidAt;
+    private Long paymentId;
+    private String status;
+    private String statusName;
+}
diff --git a/ga-core/src/main/java/com/ga/core/vo/installment/InstallmentPlanSearchParam.java b/ga-core/src/main/java/com/ga/core/vo/installment/InstallmentPlanSearchParam.java
new file mode 100644
index 0000000..fbae505
--- /dev/null
+++ b/ga-core/src/main/java/com/ga/core/vo/installment/InstallmentPlanSearchParam.java
@@ -0,0 +1,14 @@
+package com.ga.core.vo.installment;
+
+import com.ga.common.model.SearchParam;
+import lombok.Data;
+import lombok.EqualsAndHashCode;
+
+@Data
+@EqualsAndHashCode(callSuper = true)
+public class InstallmentPlanSearchParam extends SearchParam {
+    private Long contractId;
+    private String settleMonth;
+    private String status;
+    private Integer planYear;
+}
diff --git a/ga-core/src/main/java/com/ga/core/vo/installment/InstallmentPlanVO.java b/ga-core/src/main/java/com/ga/core/vo/installment/InstallmentPlanVO.java
new file mode 100644
index 0000000..bbac84f
--- /dev/null
+++ b/ga-core/src/main/java/com/ga/core/vo/installment/InstallmentPlanVO.java
@@ -0,0 +1,25 @@
+package com.ga.core.vo.installment;
+
+import lombok.Data;
+
+import java.math.BigDecimal;
+import java.time.LocalDateTime;
+
+@Data
+public class InstallmentPlanVO {
+    private Long planId;
+    private Long contractId;
+    private Integer planYear;        // 1~7
+    private Integer planMonth;       // 1~12
+    private String settleMonth;      // YYYYMM
+    private BigDecimal expectedAmount;
+    private BigDecimal paidAmount;
+    private LocalDateTime paidAt;
+    private Long paymentId;
+    private String status;
+
+    private LocalDateTime createdAt;
+    private Long createdBy;
+    private LocalDateTime updatedAt;
+    private Long updatedBy;
+}
diff --git a/ga-core/src/main/java/com/ga/core/vo/installment/InstallmentRatioResp.java b/ga-core/src/main/java/com/ga/core/vo/installment/InstallmentRatioResp.java
new file mode 100644
index 0000000..df00ed8
--- /dev/null
+++ b/ga-core/src/main/java/com/ga/core/vo/installment/InstallmentRatioResp.java
@@ -0,0 +1,18 @@
+package com.ga.core.vo.installment;
+
+import lombok.Data;
+
+import java.math.BigDecimal;
+import java.time.LocalDate;
+
+@Data
+public class InstallmentRatioResp {
+    private Long ratioId;
+    private String productCategory;
+    private String productCategoryName;
+    private Integer planYear;
+    private BigDecimal ratioPercent;
+    private LocalDate effectiveFrom;
+    private LocalDate effectiveTo;
+    private Boolean isActive;
+}
diff --git a/ga-core/src/main/java/com/ga/core/vo/installment/InstallmentRatioSaveReq.java b/ga-core/src/main/java/com/ga/core/vo/installment/InstallmentRatioSaveReq.java
new file mode 100644
index 0000000..88eb5f0
--- /dev/null
+++ b/ga-core/src/main/java/com/ga/core/vo/installment/InstallmentRatioSaveReq.java
@@ -0,0 +1,30 @@
+package com.ga.core.vo.installment;
+
+import jakarta.validation.constraints.Max;
+import jakarta.validation.constraints.Min;
+import jakarta.validation.constraints.NotNull;
+import jakarta.validation.constraints.Positive;
+import lombok.Data;
+
+import java.math.BigDecimal;
+import java.time.LocalDate;
+
+@Data
+public class InstallmentRatioSaveReq {
+
+    private String productCategory;   // NULL = 전체 상품
+
+    @NotNull(message = "분급 연차는 필수입니다")
+    @Min(value = 1, message = "분급 연차는 1 이상이어야 합니다")
+    @Max(value = 7, message = "분급 연차는 7 이하여야 합니다")
+    private Integer planYear;
+
+    @NotNull(message = "비율은 필수입니다")
+    @Positive(message = "비율은 양수여야 합니다")
+    private BigDecimal ratioPercent;
+
+    @NotNull(message = "적용 시작일은 필수입니다")
+    private LocalDate effectiveFrom;
+
+    private LocalDate effectiveTo;
+}
diff --git a/ga-core/src/main/java/com/ga/core/vo/installment/InstallmentRatioSearchParam.java b/ga-core/src/main/java/com/ga/core/vo/installment/InstallmentRatioSearchParam.java
new file mode 100644
index 0000000..06e4143
--- /dev/null
+++ b/ga-core/src/main/java/com/ga/core/vo/installment/InstallmentRatioSearchParam.java
@@ -0,0 +1,13 @@
+package com.ga.core.vo.installment;
+
+import com.ga.common.model.SearchParam;
+import lombok.Data;
+import lombok.EqualsAndHashCode;
+
+@Data
+@EqualsAndHashCode(callSuper = true)
+public class InstallmentRatioSearchParam extends SearchParam {
+    private String productCategory;
+    private Integer planYear;
+    private String effectiveDate;   // YYYY-MM-DD — 해당 날짜 유효 비율 필터
+}
diff --git a/ga-core/src/main/java/com/ga/core/vo/installment/InstallmentRatioVO.java b/ga-core/src/main/java/com/ga/core/vo/installment/InstallmentRatioVO.java
new file mode 100644
index 0000000..6e3a678
--- /dev/null
+++ b/ga-core/src/main/java/com/ga/core/vo/installment/InstallmentRatioVO.java
@@ -0,0 +1,23 @@
+package com.ga.core.vo.installment;
+
+import lombok.Data;
+
+import java.math.BigDecimal;
+import java.time.LocalDate;
+import java.time.LocalDateTime;
+
+@Data
+public class InstallmentRatioVO {
+    private Long ratioId;
+    private String productCategory;   // NULL = ALL 상품
+    private Integer planYear;         // 1~7
+    private BigDecimal ratioPercent;
+    private LocalDate effectiveFrom;
+    private LocalDate effectiveTo;    // NULL = 현재 유효
+    private Boolean isActive;
+
+    private LocalDateTime createdAt;
+    private Long createdBy;
+    private LocalDateTime updatedAt;
+    private Long updatedBy;
+}
diff --git a/ga-core/src/main/java/com/ga/core/vo/installment/InstallmentStatus.java b/ga-core/src/main/java/com/ga/core/vo/installment/InstallmentStatus.java
new file mode 100644
index 0000000..3786617
--- /dev/null
+++ b/ga-core/src/main/java/com/ga/core/vo/installment/InstallmentStatus.java
@@ -0,0 +1,7 @@
+package com.ga.core.vo.installment;
+
+public enum InstallmentStatus {
+    SCHEDULED, PAID, DEFERRED, CANCELLED;
+
+    public String code() { return this.name(); }
+}
diff --git a/ga-core/src/main/resources/mapper/installment/InstallmentPlanMapper.xml b/ga-core/src/main/resources/mapper/installment/InstallmentPlanMapper.xml
new file mode 100644
index 0000000..ef0713b
--- /dev/null
+++ b/ga-core/src/main/resources/mapper/installment/InstallmentPlanMapper.xml
@@ -0,0 +1,191 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
+        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
+<mapper namespace="com.ga.core.mapper.installment.InstallmentPlanMapper">
+
+    <!-- ==================== ResultMap ==================== -->
+
+    <!-- installment_plan 테이블 1:1 매핑 (CUD용) -->
+    <resultMap id="VOMap" type="com.ga.core.vo.installment.InstallmentPlanVO">
+        <id  property="planId"           column="plan_id"/>
+        <result property="contractId"        column="contract_id"/>
+        <result property="planYear"          column="plan_year"/>
+        <result property="planMonth"         column="plan_month"/>
+        <result property="settleMonth"       column="settle_month"/>
+        <result property="expectedAmount"    column="expected_amount"/>
+        <result property="paidAmount"        column="paid_amount"/>
+        <result property="paidAt"            column="paid_at"/>
+        <result property="paymentId"         column="payment_id"/>
+        <result property="status"            column="status"/>
+        <result property="createdAt"         column="created_at"/>
+        <result property="createdBy"         column="created_by"/>
+        <result property="updatedAt"         column="updated_at"/>
+        <result property="updatedBy"         column="updated_by"/>
+    </resultMap>
+
+    <!-- 조인 결과 포함 API 응답용 -->
+    <resultMap id="RespMap" type="com.ga.core.vo.installment.InstallmentPlanResp">
+        <id  property="planId"           column="plan_id"/>
+        <result property="contractId"        column="contract_id"/>
+        <result property="policyNo"          column="policy_no"/>
+        <result property="productName"       column="product_name"/>
+        <result property="agentId"           column="agent_id"/>
+        <result property="agentName"         column="agent_name"/>
+        <result property="planYear"          column="plan_year"/>
+        <result property="planMonth"         column="plan_month"/>
+        <result property="settleMonth"       column="settle_month"/>
+        <result property="expectedAmount"    column="expected_amount"/>
+        <result property="paidAmount"        column="paid_amount"/>
+        <result property="paidAt"            column="paid_at"/>
+        <result property="paymentId"         column="payment_id"/>
+        <result property="status"            column="status"/>
+        <result property="statusName"        column="status_name"/>
+    </resultMap>
+
+    <!-- ==================== 공통 SELECT 컬럼 ==================== -->
+
+    <sql id="selectRespCols">
+        p.plan_id,
+        p.contract_id,
+        c.policy_no,
+        pr.product_name,
+        c.agent_id,
+        a.agent_name,
+        p.plan_year,
+        p.plan_month,
+        p.settle_month,
+        p.expected_amount,
+        p.paid_amount,
+        p.paid_at,
+        p.payment_id,
+        p.status,
+        (SELECT cc.code_name FROM common_code cc
+         WHERE cc.group_code = 'INSTALLMENT_STATUS' AND cc.code = p.status) AS status_name
+    </sql>
+
+    <!-- ==================== SELECT ==================== -->
+
+    <!-- 목록 조회 (검색 조건 + 페이징) -->
+    <select id="selectList" parameterType="com.ga.core.vo.installment.InstallmentPlanSearchParam"
+            resultMap="RespMap">
+        SELECT <include refid="selectRespCols"/>
+        FROM installment_plan p
+        JOIN contract c  ON c.contract_id = p.contract_id
+        JOIN product  pr ON pr.product_id = c.product_id
+        JOIN agent    a  ON a.agent_id = c.agent_id
+        <where>
+            <if test="contractId != null">
+                AND p.contract_id = #{contractId}
+            </if>
+            <if test="settleMonth != null and settleMonth != ''">
+                AND p.settle_month = #{settleMonth}
+            </if>
+            <if test="status != null and status != ''">
+                AND p.status = #{status}
+            </if>
+            <if test="planYear != null">
+                AND p.plan_year = #{planYear}
+            </if>
+        </where>
+        ORDER BY p.contract_id, p.plan_year, p.plan_month
+        <if test="pageSize != null and pageSize > 0">
+            LIMIT #{pageSize} OFFSET #{offset}
+        </if>
+    </select>
+
+    <!-- 단건 조회 (Resp: 조인 포함) -->
+    <select id="selectDetailById" resultMap="RespMap">
+        SELECT <include refid="selectRespCols"/>
+        FROM installment_plan p
+        JOIN contract c  ON c.contract_id = p.contract_id
+        JOIN product  pr ON pr.product_id = c.product_id
+        JOIN agent    a  ON a.agent_id = c.agent_id
+        WHERE p.plan_id = #{planId}
+    </select>
+
+    <!-- 단건 조회 (VO: CUD용) -->
+    <select id="selectById" resultMap="VOMap">
+        SELECT plan_id, contract_id, plan_year, plan_month, settle_month,
+               expected_amount, paid_amount, paid_at, payment_id, status,
+               created_at, created_by, updated_at, updated_by
+        FROM installment_plan
+        WHERE plan_id = #{planId}
+    </select>
+
+    <!-- 계약의 전체 분급 계획 조회 (계약 상세 화면용, 연차/월 순 정렬) -->
+    <select id="selectByContract" resultMap="VOMap">
+        SELECT plan_id, contract_id, plan_year, plan_month, settle_month,
+               expected_amount, paid_amount, paid_at, payment_id, status,
+               created_at, created_by, updated_at, updated_by
+        FROM installment_plan
+        WHERE contract_id = #{contractId}
+        ORDER BY plan_year, plan_month
+    </select>
+
+    <!-- 정산월의 SCHEDULED 분급 계획 조회 (배치 지급 처리용) -->
+    <select id="selectScheduledByMonth" resultMap="VOMap">
+        SELECT plan_id, contract_id, plan_year, plan_month, settle_month,
+               expected_amount, paid_amount, paid_at, payment_id, status,
+               created_at, created_by, updated_at, updated_by
+        FROM installment_plan
+        WHERE settle_month = #{settleMonth}
+          AND status = 'SCHEDULED'
+        ORDER BY contract_id, plan_year, plan_month
+    </select>
+
+    <!-- ==================== INSERT ==================== -->
+
+    <insert id="insert" parameterType="com.ga.core.vo.installment.InstallmentPlanVO"
+            useGeneratedKeys="true" keyProperty="planId">
+        INSERT INTO installment_plan (
+            contract_id, plan_year, plan_month, settle_month,
+            expected_amount, paid_amount, status,
+            created_at, created_by
+        ) VALUES (
+            #{contractId}, #{planYear}, #{planMonth}, #{settleMonth},
+            #{expectedAmount}, COALESCE(#{paidAmount}, 0),
+            COALESCE(#{status}, 'SCHEDULED'),
+            NOW(), #{createdBy}
+        )
+    </insert>
+
+    <!-- 7년치 분급 계획 일괄 생성 (계약 등록 시 배치 처리) -->
+    <insert id="insertBatch">
+        INSERT INTO installment_plan (
+            contract_id, plan_year, plan_month, settle_month,
+            expected_amount, paid_amount, status,
+            created_at, created_by
+        ) VALUES
+        <foreach collection="list" item="p" separator=",">
+            (#{p.contractId}, #{p.planYear}, #{p.planMonth}, #{p.settleMonth},
+             #{p.expectedAmount}, COALESCE(#{p.paidAmount}, 0),
+             COALESCE(#{p.status}, 'SCHEDULED'),
+             NOW(), #{p.createdBy})
+        </foreach>
+    </insert>
+
+    <!-- ==================== UPDATE ==================== -->
+
+    <update id="update" parameterType="com.ga.core.vo.installment.InstallmentPlanVO">
+        UPDATE installment_plan
+        <set>
+            <if test="settleMonth != null and settleMonth != ''">settle_month = #{settleMonth},</if>
+            <if test="expectedAmount != null">expected_amount = #{expectedAmount},</if>
+            <if test="paidAmount != null">paid_amount = #{paidAmount},</if>
+            <if test="paidAt != null">paid_at = #{paidAt},</if>
+            <if test="paymentId != null">payment_id = #{paymentId},</if>
+            <if test="status != null and status != ''">status = #{status},</if>
+            updated_at = NOW(),
+            updated_by = #{updatedBy}
+        </set>
+        WHERE plan_id = #{planId}
+    </update>
+
+    <!-- 상태만 변경 (PAID / DEFERRED / CANCELLED) -->
+    <update id="updateStatus">
+        UPDATE installment_plan
+        SET status = #{status}, updated_at = NOW()
+        WHERE plan_id = #{planId}
+    </update>
+
+</mapper>
diff --git a/ga-core/src/main/resources/mapper/installment/InstallmentRatioMapper.xml b/ga-core/src/main/resources/mapper/installment/InstallmentRatioMapper.xml
new file mode 100644
index 0000000..b896177
--- /dev/null
+++ b/ga-core/src/main/resources/mapper/installment/InstallmentRatioMapper.xml
@@ -0,0 +1,155 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
+        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
+<mapper namespace="com.ga.core.mapper.installment.InstallmentRatioMapper">
+
+    <!-- ==================== ResultMap ==================== -->
+
+    <!-- installment_ratio 테이블 1:1 매핑 (CUD용) -->
+    <resultMap id="VOMap" type="com.ga.core.vo.installment.InstallmentRatioVO">
+        <id  property="ratioId"          column="ratio_id"/>
+        <result property="productCategory"   column="product_category"/>
+        <result property="planYear"          column="plan_year"/>
+        <result property="ratioPercent"      column="ratio_percent"/>
+        <result property="effectiveFrom"     column="effective_from"/>
+        <result property="effectiveTo"       column="effective_to"/>
+        <result property="isActive"          column="is_active"/>
+        <result property="createdAt"         column="created_at"/>
+        <result property="createdBy"         column="created_by"/>
+        <result property="updatedAt"         column="updated_at"/>
+        <result property="updatedBy"         column="updated_by"/>
+    </resultMap>
+
+    <!-- 코드명 포함 API 응답용 -->
+    <resultMap id="RespMap" type="com.ga.core.vo.installment.InstallmentRatioResp">
+        <id  property="ratioId"              column="ratio_id"/>
+        <result property="productCategory"       column="product_category"/>
+        <result property="productCategoryName"   column="product_category_name"/>
+        <result property="planYear"              column="plan_year"/>
+        <result property="ratioPercent"          column="ratio_percent"/>
+        <result property="effectiveFrom"         column="effective_from"/>
+        <result property="effectiveTo"           column="effective_to"/>
+        <result property="isActive"              column="is_active"/>
+    </resultMap>
+
+    <!-- ==================== 공통 SELECT 컬럼 ==================== -->
+
+    <sql id="selectRespCols">
+        r.ratio_id,
+        r.product_category,
+        (SELECT cc.code_name FROM common_code cc
+         WHERE cc.group_code = 'PRODUCT_CATEGORY' AND cc.code = r.product_category) AS product_category_name,
+        r.plan_year,
+        r.ratio_percent,
+        r.effective_from,
+        r.effective_to,
+        r.is_active
+    </sql>
+
+    <!-- ==================== SELECT ==================== -->
+
+    <!-- 목록 조회 (검색 조건 + 페이징) -->
+    <select id="selectList" parameterType="com.ga.core.vo.installment.InstallmentRatioSearchParam"
+            resultMap="RespMap">
+        SELECT <include refid="selectRespCols"/>
+        FROM installment_ratio r
+        <where>
+            <if test="productCategory != null and productCategory != ''">
+                AND r.product_category = #{productCategory}
+            </if>
+            <if test="planYear != null">
+                AND r.plan_year = #{planYear}
+            </if>
+            <if test="effectiveDate != null and effectiveDate != ''">
+                AND r.effective_from &lt;= #{effectiveDate}::DATE
+                AND (r.effective_to IS NULL OR r.effective_to >= #{effectiveDate}::DATE)
+            </if>
+        </where>
+        ORDER BY r.plan_year, r.effective_from DESC
+        <if test="pageSize != null and pageSize > 0">
+            LIMIT #{pageSize} OFFSET #{offset}
+        </if>
+    </select>
+
+    <!-- 단건 조회 (Resp: 코드명 포함) -->
+    <select id="selectDetailById" resultMap="RespMap">
+        SELECT <include refid="selectRespCols"/>
+        FROM installment_ratio r
+        WHERE r.ratio_id = #{ratioId}
+    </select>
+
+    <!-- 단건 조회 (VO: CUD용) -->
+    <select id="selectById" resultMap="VOMap">
+        SELECT ratio_id, product_category, plan_year, ratio_percent,
+               effective_from, effective_to, is_active,
+               created_at, created_by, updated_at, updated_by
+        FROM installment_ratio
+        WHERE ratio_id = #{ratioId}
+    </select>
+
+    <!--
+        특정 날짜에 유효한 분급 비율 1건 조회.
+        product_category NULL은 전체 상품 적용 행이므로
+        NULL 매개변수가 들어오면 IS NULL 조건으로 처리.
+        effective_from DESC 정렬로 최신 개정본 우선 반환.
+    -->
+    <select id="selectActive" resultMap="VOMap">
+        SELECT ratio_id, product_category, plan_year, ratio_percent,
+               effective_from, effective_to, is_active,
+               created_at, created_by, updated_at, updated_by
+        FROM installment_ratio
+        WHERE plan_year = #{planYear}
+          AND (product_category = #{productCategory}
+               OR (#{productCategory} IS NULL AND product_category IS NULL))
+          AND is_active = TRUE
+          AND effective_from &lt;= #{baseDate}::DATE
+          AND (effective_to IS NULL OR effective_to >= #{baseDate}::DATE)
+        ORDER BY effective_from DESC
+        LIMIT 1
+    </select>
+
+    <!-- 1~7년 차 전체 비율 조회 (분급 계획 일괄 생성 시 사용) -->
+    <select id="selectAllActiveRatios" resultMap="VOMap">
+        SELECT ratio_id, product_category, plan_year, ratio_percent,
+               effective_from, effective_to, is_active,
+               created_at, created_by, updated_at, updated_by
+        FROM installment_ratio
+        WHERE (product_category = #{productCategory}
+               OR (#{productCategory} IS NULL AND product_category IS NULL))
+          AND is_active = TRUE
+          AND effective_from &lt;= #{baseDate}::DATE
+          AND (effective_to IS NULL OR effective_to >= #{baseDate}::DATE)
+        ORDER BY plan_year
+    </select>
+
+    <!-- ==================== INSERT ==================== -->
+
+    <insert id="insert" parameterType="com.ga.core.vo.installment.InstallmentRatioVO"
+            useGeneratedKeys="true" keyProperty="ratioId">
+        INSERT INTO installment_ratio (
+            product_category, plan_year, ratio_percent,
+            effective_from, effective_to, is_active,
+            created_at, created_by
+        ) VALUES (
+            #{productCategory}, #{planYear}, #{ratioPercent},
+            #{effectiveFrom}, #{effectiveTo}, COALESCE(#{isActive}, TRUE),
+            NOW(), #{createdBy}
+        )
+    </insert>
+
+    <!-- ==================== UPDATE ==================== -->
+
+    <update id="update" parameterType="com.ga.core.vo.installment.InstallmentRatioVO">
+        UPDATE installment_ratio
+        <set>
+            <if test="ratioPercent != null">ratio_percent = #{ratioPercent},</if>
+            <if test="effectiveFrom != null">effective_from = #{effectiveFrom},</if>
+            <if test="effectiveTo != null">effective_to = #{effectiveTo},</if>
+            <if test="isActive != null">is_active = #{isActive},</if>
+            updated_at = NOW(),
+            updated_by = #{updatedBy}
+        </set>
+        WHERE ratio_id = #{ratioId}
+    </update>
+
+</mapper>