diff --git a/packages/react-i18n/CHANGELOG.md b/packages/react-i18n/CHANGELOG.md
index 8c58c73cd5..206b0678bc 100644
--- a/packages/react-i18n/CHANGELOG.md
+++ b/packages/react-i18n/CHANGELOG.md
@@ -6,7 +6,13 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/).
 
 ---
 
-<!-- ## [Unreleased] -->
+## [Unreleased]
+
+### Fixed
+
+- Fixed memory leaks when server-side rendering for `Intl.DateTimeFormat.format()` and `Intl.NumberFormat.format()` ([#1287](https://github.com/Shopify/quilt/pull/1287))
+
+---
 
 ### Fixed
 
diff --git a/packages/react-i18n/src/i18n.ts b/packages/react-i18n/src/i18n.ts
index 4c65d95dc9..b4940ace80 100644
--- a/packages/react-i18n/src/i18n.ts
+++ b/packages/react-i18n/src/i18n.ts
@@ -1,4 +1,5 @@
 import {
+  formatDate,
   isLessThanOneHourAgo,
   isLessThanOneMinuteAgo,
   isLessThanOneWeekAgo,
@@ -7,7 +8,6 @@ import {
   isYesterday,
   TimeUnit,
 } from '@shopify/dates';
-import {memoize as memoizeFn} from '@shopify/function-enhancers';
 import {memoize} from '@shopify/decorators';
 import {languageFromLocale, regionFromLocale} from '@shopify/i18n';
 
@@ -61,12 +61,6 @@ const DECIMAL_NOT_SUPPORTED = 'N/A';
 const PERIOD = '.';
 const DECIMAL_VALUE_FOR_CURRENCIES_WITHOUT_DECIMALS = '00';
 
-const memoizedDateTimeFormatter = memoizeFn(
-  dateTimeFormatter,
-  (locale: string, options: Intl.DateTimeFormatOptions = {}) =>
-    `${locale}${JSON.stringify(options)}`,
-);
-
 export class I18n {
   readonly locale: string;
   readonly pseudolocalize: boolean | string;
@@ -296,13 +290,6 @@ export class I18n {
     const {locale, defaultTimezone} = this;
     const {timeZone = defaultTimezone} = options;
 
-    // Etc/GMT+12 is not supported in most browsers and there is no equivalent fallback
-    if (timeZone === 'Etc/GMT+12') {
-      const adjustedDate = new Date(date.valueOf() - 12 * 60 * 60 * 1000);
-
-      return this.formatDate(adjustedDate, {...options, timeZone: 'UTC'});
-    }
-
     const {style = undefined, ...formatOptions} = options || {};
 
     if (style) {
@@ -311,10 +298,7 @@ export class I18n {
         : this.formatDate(date, {...formatOptions, ...dateStyle[style]});
     }
 
-    return memoizedDateTimeFormatter(locale, {
-      timeZone,
-      ...formatOptions,
-    }).format(date);
+    return formatDate(date, locale, {...formatOptions, timeZone});
   }
 
   ordinal(amount: number) {
@@ -566,10 +550,3 @@ function isTranslateOptions(
 function defaultOnError(error: I18nError) {
   throw error;
 }
-
-function dateTimeFormatter(
-  locale: string,
-  options: Intl.DateTimeFormatOptions = {},
-) {
-  return new Intl.DateTimeFormat(locale, options);
-}
diff --git a/packages/react-i18n/src/utilities/translate.tsx b/packages/react-i18n/src/utilities/translate.tsx
index 464f866a12..66d3d23ee9 100644
--- a/packages/react-i18n/src/utilities/translate.tsx
+++ b/packages/react-i18n/src/utilities/translate.tsx
@@ -17,6 +17,17 @@ const MISSING_TRANSLATION = Symbol('Missing translation');
 const PLURALIZATION_KEY_NAME = 'count';
 const SEPARATOR = '.';
 
+const numberFormats = new Map();
+export const memoizedNumberFormatter = function(locale, options = {}) {
+  const key = numberFormatCacheKey(locale, options);
+  if (numberFormats.has(key)) {
+    return numberFormats.get(key);
+  }
+  const i = new Intl.NumberFormat(locale, options);
+  numberFormats.set(key, i);
+  return i;
+};
+
 export const PSEUDOTRANSLATE_OPTIONS: PseudotranslateOptions = {
   startDelimiter: '{',
   endDelimiter: '}',
@@ -30,19 +41,13 @@ export interface TranslateOptions<Replacements = {}> {
   pseudotranslate?: boolean | string;
 }
 
-function numberFormatter(
+function numberFormatCacheKey(
   locale: string,
   options: Intl.NumberFormatOptions = {},
 ) {
-  return new Intl.NumberFormat(locale, options);
+  return `${locale}${JSON.stringify(options)}`;
 }
 
-export const memoizedNumberFormatter = memoizeFn(
-  numberFormatter,
-  (locale: string, options: Intl.NumberFormatOptions = {}) =>
-    `${locale}${JSON.stringify(options)}`,
-);
-
 function pluralRules(locale: string, options: Intl.PluralRulesOptions = {}) {
   return new Intl.PluralRules(locale, options);
 }