diff --git a/api/scripts/bigint/change-answers-id-type-to-bigint-with-downtime.js b/api/scripts/bigint/change-answers-id-type-to-bigint-with-downtime.js
new file mode 100644
index 00000000000..976ecdcfc33
--- /dev/null
+++ b/api/scripts/bigint/change-answers-id-type-to-bigint-with-downtime.js
@@ -0,0 +1,42 @@
+require('dotenv').config();
+const { knex } = require('../../db/knex-database-connection');
+const logger = require('../../lib/infrastructure/logger');
+
+const changeAnswerIdTypeToBigint = async () => {
+  await knex.transaction(async (trx) => {
+    logger.info('Altering knowledge-elements.answerId type to BIGINT - In progress');
+    await knex.raw(`ALTER TABLE "knowledge-elements" ALTER COLUMN "answerId" TYPE BIGINT`).transacting(trx);
+    logger.info('Altering knowledge-elements.answerId type to BIGINT - Done');
+
+    logger.info('Altering flash-assessment-results.answerId type to BIGINT - In progress');
+    await knex.raw(`ALTER TABLE "flash-assessment-results" ALTER COLUMN "answerId" TYPE BIGINT`).transacting(trx);
+    logger.info('Altering flash-assessment-results.answerId type to BIGINT - Done');
+
+    logger.info('Altering answers.id type to BIGINT - In progress');
+    await knex.raw(`ALTER TABLE "answers" ALTER COLUMN "id" TYPE BIGINT`).transacting(trx);
+    logger.info('Altering answers.id type to BIGINT - Done');
+
+    logger.info('Altering answers_id_seq type to BIGINT - In progress');
+    await knex.raw(`ALTER SEQUENCE "answers_id_seq" AS BIGINT`).transacting(trx);
+    logger.info('Altering answers_id_seq type to BIGINT - Done');
+  });
+};
+
+const preventOneOffContainerTimeout = () => {
+  setInterval(() => {
+    logger.info('alive');
+  }, 1000);
+};
+
+(async () => {
+  try {
+    preventOneOffContainerTimeout();
+    await changeAnswerIdTypeToBigint();
+    process.exit(0);
+  } catch (error) {
+    logger.fatal(error);
+    process.exit(1);
+  }
+})();
+
+module.exports = { changeAnswerIdTypeToBigint };
diff --git a/api/tests/acceptance/scripts/bigint/change-answers-id-type-to-bigint-with-downtime_test.js b/api/tests/acceptance/scripts/bigint/change-answers-id-type-to-bigint-with-downtime_test.js
new file mode 100644
index 00000000000..65e5227edf0
--- /dev/null
+++ b/api/tests/acceptance/scripts/bigint/change-answers-id-type-to-bigint-with-downtime_test.js
@@ -0,0 +1,64 @@
+const {
+  changeAnswerIdTypeToBigint,
+} = require('../../../../scripts/bigint/change-answers-id-type-to-bigint-with-downtime');
+const { expect, knex } = require('../../../test-helper');
+const DatabaseBuilder = require('../../../../db/database-builder/database-builder');
+const databaseBuilder = new DatabaseBuilder({ knex });
+
+describe('#changeAnswerIdTypeToBigint', function () {
+  let answerIdInsertedBeforeSwitch;
+
+  it('should insert answer with an id bigger than the maximum integer type value', async function () {
+    // when
+    await changeAnswerIdTypeToBigint();
+    const maxValueBigIntType = '9223372036854775807';
+    const { id: assessmentId } = databaseBuilder.factory.buildAssessment();
+    const { id: answerId } = databaseBuilder.factory.buildAnswer({ id: maxValueBigIntType, assessmentId });
+    databaseBuilder.factory.buildKnowledgeElement({ assessmentId, answerId });
+    await databaseBuilder.commit();
+
+    // then
+    expect(answerId).to.be.equal(maxValueBigIntType);
+  });
+
+  it('should change type of answer sequence from integer to bigint', async function () {
+    // when
+    await changeAnswerIdTypeToBigint();
+
+    // then
+    const { rows: sequenceDataType } = await knex.raw(
+      `SELECT data_type FROM information_schema.sequences WHERE sequence_name = 'answers_id_seq'`
+    );
+    expect(sequenceDataType[0]['data_type']).to.equal('bigint');
+  });
+
+  it('should sequence are correctly reassigned', async function () {
+    // given
+    await changeAnswerIdTypeToBigint();
+
+    // when
+    const [{ id: answerIdInsertedAfterSwitch }] = await knex('answers')
+      .insert({
+        value: 'Some value for answer',
+        result: 'Some result for answer',
+        challengeId: 'rec123ABC',
+        createdAt: new Date('2020-01-01'),
+        updatedAt: new Date('2020-01-02'),
+        resultDetails: 'Some result details for answer.',
+        timeSpent: 30,
+      })
+      .returning('id');
+
+    // then
+    expect(answerIdInsertedAfterSwitch).to.equal(answerIdInsertedBeforeSwitch + 1);
+  });
+
+  afterEach(async function () {
+    await knex.transaction(async (trx) => {
+      await knex.raw(`ALTER TABLE "knowledge-elements" ALTER COLUMN "answerId" TYPE INTEGER`).transacting(trx);
+      await knex.raw(`ALTER TABLE "flash-assessment-results" ALTER COLUMN "answerId" TYPE INTEGER`).transacting(trx);
+      await knex.raw(`ALTER TABLE "answers" ALTER COLUMN "id" TYPE INTEGER`).transacting(trx);
+      await knex.raw(`ALTER SEQUENCE "answers_id_seq" AS INTEGER`).transacting(trx);
+    });
+  });
+});