diff --git a/changelog/fix-8926-localise-vat-details-modal b/changelog/fix-8926-localise-vat-details-modal
new file mode 100644
index 00000000000..4c351552f7e
--- /dev/null
+++ b/changelog/fix-8926-localise-vat-details-modal
@@ -0,0 +1,4 @@
+Significance: minor
+Type: add
+
+Support adding tax details (corporate number) for Japan merchants (so can generate tax documents for consumption tax, aka VAT).
diff --git a/client/documents/list/test/index.tsx b/client/documents/list/test/index.tsx
index a917edaf108..c54cf7a02c8 100644
--- a/client/documents/list/test/index.tsx
+++ b/client/documents/list/test/index.tsx
@@ -238,20 +238,24 @@ describe( 'Document download button', () => {
 				expect( window.open ).not.toHaveBeenCalled();
 			} );
 
-			it( 'should open the VAT form modal', () => {
+			it( 'should open the tax details modal', () => {
 				// Make sure the modal is not opened before clicking on the button.
 				expect(
-					screen.queryByRole( 'dialog', { name: 'VAT details' } )
+					screen.queryByRole( 'dialog', {
+						name: 'Set your tax details',
+					} )
 				).toBeNull();
 
 				user.click( downloadButton );
 
 				expect(
-					screen.getByRole( 'dialog', { name: 'VAT details' } )
+					screen.getByRole( 'dialog', {
+						name: 'Set your tax details',
+					} )
 				).toBeVisible();
 			} );
 
-			describe( 'after the VAT details are submitted', () => {
+			describe( 'after the tax details are submitted', () => {
 				beforeEach( () => {
 					user.click( downloadButton );
 
@@ -260,7 +264,9 @@ describe( 'Document download button', () => {
 
 				it( 'should close the modal', () => {
 					expect(
-						screen.queryByRole( 'dialog', { name: 'VAT details' } )
+						screen.queryByRole( 'dialog', {
+							name: 'Set your tax details',
+						} )
 					).toBeNull();
 				} );
 
diff --git a/client/vat/form-modal/index.tsx b/client/vat/form-modal/index.tsx
index 42470fe45bc..56ddcda2833 100644
--- a/client/vat/form-modal/index.tsx
+++ b/client/vat/form-modal/index.tsx
@@ -24,7 +24,7 @@ const VatFormModal = ( {
 } ): JSX.Element | null => {
 	return isModalOpen ? (
 		<Modal
-			title={ __( 'VAT details', 'woocommerce-payments' ) }
+			title={ __( 'Set your tax details', 'woocommerce-payments' ) }
 			onRequestClose={ () => setModalOpen( false ) }
 		>
 			<VatForm onCompleted={ onCompleted } />
diff --git a/client/vat/form-modal/test/__snapshots__/index.tsx.snap b/client/vat/form-modal/test/__snapshots__/index.tsx.snap
index f790a7c8b87..ff5d063931f 100644
--- a/client/vat/form-modal/test/__snapshots__/index.tsx.snap
+++ b/client/vat/form-modal/test/__snapshots__/index.tsx.snap
@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`VAT form modal should render the VAT Form 1`] = `
+exports[`Tax details modal should render the VAT Form 1`] = `
 <div
   aria-labelledby="components-modal-header-1"
   class="components-modal__frame"
@@ -21,7 +21,7 @@ exports[`VAT form modal should render the VAT Form 1`] = `
           class="components-modal__header-heading"
           id="components-modal-header-1"
         >
-          VAT details
+          Set your tax details
         </h1>
       </div>
       <button
diff --git a/client/vat/form-modal/test/index.tsx b/client/vat/form-modal/test/index.tsx
index 77586023bb9..abfe43e8b6f 100644
--- a/client/vat/form-modal/test/index.tsx
+++ b/client/vat/form-modal/test/index.tsx
@@ -15,7 +15,7 @@ import VatForm from '../../form';
 
 jest.mock( '../../form', () => jest.fn() );
 
-describe( 'VAT form modal', () => {
+describe( 'Tax details modal', () => {
 	beforeEach( () => {
 		jest.mocked( VatForm ).mockReturnValue( <p>VAT Form</p> );
 	} );
@@ -29,7 +29,7 @@ describe( 'VAT form modal', () => {
 			/>
 		);
 		expect(
-			screen.getByRole( 'dialog', { name: 'VAT details' } )
+			screen.getByRole( 'dialog', { name: 'Set your tax details' } )
 		).toBeVisible();
 	} );
 
@@ -42,7 +42,7 @@ describe( 'VAT form modal', () => {
 			/>
 		);
 		expect(
-			screen.queryByRole( 'dialog', { name: 'VAT details' } )
+			screen.queryByRole( 'dialog', { name: 'Set your tax details' } )
 		).toBeNull();
 	} );
 
@@ -55,7 +55,7 @@ describe( 'VAT form modal', () => {
 			/>
 		);
 		expect(
-			screen.getByRole( 'dialog', { name: 'VAT details' } )
+			screen.getByRole( 'dialog', { name: 'Set your tax details' } )
 		).toMatchSnapshot();
 	} );
 
@@ -82,7 +82,7 @@ describe( 'VAT form modal', () => {
 		);
 
 		expect(
-			screen.queryByRole( 'dialog', { name: 'VAT details' } )
+			screen.queryByRole( 'dialog', { name: 'Set your tax details' } )
 		).toBeNull();
 	} );
 } );
diff --git a/client/vat/form/tasks/vat-number-task.tsx b/client/vat/form/tasks/vat-number-task.tsx
index 37d5c6fb15c..d1c0349bc69 100644
--- a/client/vat/form/tasks/vat-number-task.tsx
+++ b/client/vat/form/tasks/vat-number-task.tsx
@@ -9,7 +9,7 @@ import {
 	Notice,
 	TextControl,
 } from '@wordpress/components';
-import { __ } from '@wordpress/i18n';
+import { __, sprintf } from '@wordpress/i18n';
 import React, { useContext, useState } from 'react';
 import CollapsibleBody from 'wcpay/additional-methods-setup/wizard/collapsible-body';
 import WizardTaskItem from 'wcpay/additional-methods-setup/wizard/task-item';
@@ -22,8 +22,14 @@ import apiFetch from '@wordpress/api-fetch';
 import { VatError, VatFormOnCompleted, VatValidationResult } from '../../types';
 import '../style.scss';
 
+/**
+ * These country-specific getters may belong on server.
+ */
 const getVatPrefix = () => {
 	switch ( wcpaySettings.accountStatus.country ) {
+		case 'JP':
+			// Corporate numbers are not prefixed.
+			return '';
 		case 'GR':
 			return 'EL ';
 		case 'CH':
@@ -33,6 +39,51 @@ const getVatPrefix = () => {
 	}
 };
 
+const getVatTaxIDName = () => {
+	switch ( wcpaySettings.accountStatus.country ) {
+		case 'JP':
+			return __( 'Corporate Number', 'woocommerce-payments' );
+		default:
+			return __( 'VAT Number', 'woocommerce-payments' );
+	}
+};
+
+const getVatTaxIDRequirementHint = () => {
+	switch ( wcpaySettings.accountStatus.country ) {
+		case 'JP':
+			// Leaving this blank intentionally, as I don't know what the requirements are in JP.
+			// Better to add this info later than clutter the dialog with vague/assumed legal requirements.
+			return __( '', 'woocommerce-payments' );
+		default:
+			// Note: this message is a little alarming and doesn't provide guidance for confused merchants.
+			// Logged: https://github.com/Automattic/woocommerce-payments/issues/9161.
+			return __(
+				"If your sales exceed the VAT threshold for your country, you're required to register for a VAT Number.",
+				'woocommerce-payments'
+			);
+	}
+};
+
+const getVatTaxIDValidationHint = () => {
+	switch ( wcpaySettings.accountStatus.country ) {
+		case 'JP':
+			return __(
+				'A 13 digit number, for example 1234567890123.',
+				'woocommerce-payments'
+			);
+		default:
+			return __(
+				'8 to 12 digits with your country code prefix, for example DE 123456789.',
+				'woocommerce-payments'
+			);
+	}
+};
+
+/**
+ * A two-step "task" for obtaining merchant's tax details.
+ *
+ * @param {VatFormOnCompleted} props.onCompleted - Callback to provide tax details on submit.
+ */
 export const VatNumberTask = ( {
 	onCompleted,
 }: {
@@ -95,17 +146,24 @@ export const VatNumberTask = ( {
 	};
 
 	return (
+		// Note: the VAT ID name is parameterised in strings below.
+		// Long term, it might be better to implement a dedicated WizardTaskItem component for each tax region.
+		// This would reduce the amount of branching on country, and make it easier to view or translate the whole UX for each region.
 		<WizardTaskItem
 			index={ 1 }
-			title={ __(
-				'Update your VAT information',
-				'woocommerce-payments'
+			title={ sprintf(
+				__(
+					/* translators: %$1$s: tax ID name, e.g. VAT Number, GST Number, Corporate Number */
+					'Set your %1$s',
+					'woocommerce-payments'
+				),
+				getVatTaxIDName()
 			) }
 			className={ null }
 		>
 			<p className="wcpay-wizard-task__description-element">
 				{ __(
-					'VAT information saved on this page will be applied to all of your account’s receipts.',
+					"The information you provide here will be used for all of your account's tax documents.",
 					'woocommerce-payments'
 				) }
 			</p>
@@ -114,22 +172,22 @@ export const VatNumberTask = ( {
 				<CheckboxControl
 					checked={ isVatRegistered }
 					onChange={ setVatRegistered }
-					label={ __(
-						'I’m registered for a VAT number',
-						'woocommerce-payments'
-					) }
-					help={ __(
-						'If your sales exceed the VAT threshold for your country, you’re required to register for a VAT number.',
-						'woocommerce-payments'
+					label={ sprintf(
+						__(
+							/* translators: %$1$s: tax ID name, e.g. VAT Number, GST Number, Corporate Number */
+							"I'm registered for a %1$s",
+							'woocommerce-payments'
+						),
+						getVatTaxIDName()
 					) }
+					help={ getVatTaxIDRequirementHint() }
 				/>
 				{ isVatRegistered && (
+					// Note: this TextControl is heavily parameterised to support different regions (VAT vs GST vs Corporate Number).
+					// Long term, if we implement a dedicated WizardTaskItem component for each tax region, then this component will be simpler.
 					<TextControl
-						label={ __( 'VAT Number', 'woocommerce-payments' ) }
-						help={ __(
-							'This is 8 to 12 digits with your country code prefix, for example DE 123456789.',
-							'woocommerce-payments'
-						) }
+						label={ getVatTaxIDName() }
+						help={ getVatTaxIDValidationHint() }
 						value={ vatNumber }
 						onChange={ setVatNumber }
 					/>
diff --git a/client/vat/form/test/index.tsx b/client/vat/form/test/index.tsx
index d73a3b9a45b..d8760fa2924 100644
--- a/client/vat/form/test/index.tsx
+++ b/client/vat/form/test/index.tsx
@@ -48,17 +48,21 @@ declare const global: {
 	};
 };
 
-const countries = [
-	[ 'GB', 'GB' ],
-	[ 'DE', 'DE' ],
-	[ 'GR', 'EL' ],
-	[ 'CH', 'CHE' ],
+/**
+ * Expected prefix and tax ID name for each supported country.
+ */
+const countryTaxNumberInfo = [
+	[ 'GB', 'GB', 'VAT Number' ],
+	[ 'DE', 'DE', 'VAT Number' ],
+	[ 'GR', 'EL', 'VAT Number' ],
+	[ 'CH', 'CHE', 'VAT Number' ],
+	[ 'JP', '', 'Corporate Number' ],
 ];
 
 describe( 'VAT form', () => {
-	it.each( countries )(
+	it.each( countryTaxNumberInfo )(
 		'should display the right prefix for country %s',
-		( country, expectedPrefix ) => {
+		( country, expectedPrefix, expectedTaxIdName ) => {
 			global.wcpaySettings = {
 				accountStatus: { country: country },
 			};
@@ -66,12 +70,25 @@ describe( 'VAT form', () => {
 			render( <VatForm onCompleted={ mockOnCompleted } /> );
 
 			user.click(
-				screen.getByLabelText( 'I’m registered for a VAT number' )
+				screen.getByLabelText(
+					`I'm registered for a ${ expectedTaxIdName }`
+				)
 			);
 
-			expect(
-				screen.getByRole( 'textbox', { name: 'VAT Number' } )
-			).toHaveValue( `${ expectedPrefix } ` );
+			if ( expectedPrefix ) {
+				expect(
+					screen.getByRole( 'textbox', {
+						name: `${ expectedTaxIdName }`,
+					} )
+				).toHaveValue( `${ expectedPrefix } ` );
+			} else {
+				// Special case no prefix (JP) – the value is not necessarily empty string.
+				expect(
+					screen.getByRole( 'textbox', {
+						name: `${ expectedTaxIdName }`,
+					} )
+				).toBeEmptyDOMElement();
+			}
 		}
 	);
 } );
@@ -205,7 +222,7 @@ describe( 'VAT form', () => {
 	describe( 'when registered for VAT', () => {
 		beforeEach( () => {
 			user.click(
-				screen.getByLabelText( 'I’m registered for a VAT number' )
+				screen.getByLabelText( "I'm registered for a VAT Number" )
 			);
 		} );