diff --git a/locales-common/src/main/java/com/spotify/i18n/locales/common/impl/LocaleAffinityCalculatorBaseImpl.java b/locales-common/src/main/java/com/spotify/i18n/locales/common/impl/LocaleAffinityCalculatorBaseImpl.java
index 65e190c..95703f1 100644
--- a/locales-common/src/main/java/com/spotify/i18n/locales/common/impl/LocaleAffinityCalculatorBaseImpl.java
+++ b/locales-common/src/main/java/com/spotify/i18n/locales/common/impl/LocaleAffinityCalculatorBaseImpl.java
@@ -21,6 +21,7 @@
 package com.spotify.i18n.locales.common.impl;
 
 import static com.spotify.i18n.locales.utils.hierarchy.LocalesHierarchyUtils.isRootLocale;
+import static com.spotify.i18n.locales.utils.hierarchy.LocalesHierarchyUtils.isSameLocale;
 
 import com.google.auto.value.AutoValue;
 import com.google.common.base.Preconditions;
@@ -33,8 +34,10 @@
 import com.spotify.i18n.locales.common.LocaleAffinityCalculator;
 import com.spotify.i18n.locales.common.model.LocaleAffinity;
 import com.spotify.i18n.locales.common.model.LocaleAffinityResult;
+import com.spotify.i18n.locales.utils.language.LanguageUtils;
 import com.spotify.i18n.locales.utils.languagetag.LanguageTagUtils;
 import edu.umd.cs.findbugs.annotations.Nullable;
+import java.util.Optional;
 import java.util.Set;
 
 /**
@@ -97,12 +100,36 @@ private LocaleAffinity getAffinity(@Nullable final String languageTag) {
     if (againstLocales().isEmpty()) {
       return LocaleAffinity.NONE;
     } else {
-      int bestDistance = getBestDistance(languageTag);
-      int correspondingScore = convertDistanceToAffinityScore(bestDistance);
-      return convertScoreToLocaleAffinity(correspondingScore);
+      // We attempt to match based on corresponding spoken language first, and make use of the
+      // score-based affinity calculation as fallback.
+      if (hasSameSpokenLanguageAffinity(languageTag)) {
+        return LocaleAffinity.SAME_OR_INTERCHANGEABLE;
+      } else {
+        return calculateScoreBasedAffinity(languageTag);
+      }
     }
   }
 
+  private boolean hasSameSpokenLanguageAffinity(final String languageTag) {
+    return LanguageUtils.getSpokenLanguageLocale(languageTag)
+        .map(
+            spokenLanguageLocale ->
+                againstLocales().stream()
+                    .map(ULocale::toLanguageTag)
+                    .map(LanguageUtils::getSpokenLanguageLocale)
+                    .flatMap(Optional::stream)
+                    .anyMatch(
+                        againstSpokenLocale ->
+                            isSameLocale(spokenLanguageLocale, againstSpokenLocale)))
+        .orElse(false);
+  }
+
+  private LocaleAffinity calculateScoreBasedAffinity(String languageTag) {
+    int bestDistance = getBestDistance(languageTag);
+    int correspondingScore = convertDistanceToAffinityScore(bestDistance);
+    return convertScoreToLocaleAffinity(correspondingScore);
+  }
+
   private int getBestDistance(@Nullable final String languageTag) {
     return LanguageTagUtils.parse(languageTag)
         .map(LocaleAffinityCalculatorBaseImpl::getMaximizedLanguageScriptRegion)
diff --git a/locales-common/src/test/java/com/spotify/i18n/locales/common/impl/ReferenceLocalesCalculatorBaseImplTest.java b/locales-common/src/test/java/com/spotify/i18n/locales/common/impl/ReferenceLocalesCalculatorBaseImplTest.java
index 6a5acb2..1eebd64 100644
--- a/locales-common/src/test/java/com/spotify/i18n/locales/common/impl/ReferenceLocalesCalculatorBaseImplTest.java
+++ b/locales-common/src/test/java/com/spotify/i18n/locales/common/impl/ReferenceLocalesCalculatorBaseImplTest.java
@@ -34,6 +34,7 @@
 import com.spotify.i18n.locales.common.model.LocaleAffinity;
 import com.spotify.i18n.locales.common.model.RelatedReferenceLocale;
 import com.spotify.i18n.locales.utils.available.AvailableLocalesUtils;
+import com.spotify.i18n.locales.utils.language.LanguageUtils;
 import java.util.List;
 import java.util.Optional;
 import java.util.stream.Stream;
@@ -69,7 +70,8 @@ public void validateLocaleAffinityScoreRanges(final ULocale input) {
 
       ULocale referenceLanguageScriptOnly = getLocaleWithLanguageAndScriptOnly(referenceLocale);
 
-      if (isSameLocale(inputLanguageScriptOnly, referenceLanguageScriptOnly)) {
+      if (isSameLocale(inputLanguageScriptOnly, referenceLanguageScriptOnly)
+          || isSameSpokenLanguage(inputLanguageScriptOnly, referenceLanguageScriptOnly)) {
         assertEquals(
             SAME_OR_INTERCHANGEABLE,
             affinity,
@@ -101,6 +103,12 @@ public void validateLocaleAffinityScoreRanges(final ULocale input) {
     }
   }
 
+  private boolean isSameSpokenLanguage(
+      ULocale inputLanguageScriptOnly, ULocale referenceLanguageScriptOnly) {
+    return LanguageUtils.getSpokenLanguageLocale(inputLanguageScriptOnly.toLanguageTag())
+        .equals(LanguageUtils.getSpokenLanguageLocale(referenceLanguageScriptOnly.toLanguageTag()));
+  }
+
   private static ULocale getLocaleWithLanguageAndScriptOnly(ULocale input) {
     return new Builder()
         .setLocale(ULocale.addLikelySubtags(input))
@@ -116,10 +124,13 @@ private boolean areKnownInterchangeableLocales(ULocale inputLS, ULocale referenc
     switch (input) {
         // Bosnian and Croatian
       case "bs-Latn":
+        return reference.equals("hr-Latn");
+        // Bosnian and Croatian
+      case "bs-Cyrl":
         return reference.equals("hr-Latn");
         // Croatian and Bosnian
       case "hr-Latn":
-        return reference.equals("bs-Latn");
+        return reference.equals("bs-Latn") || reference.equals("bs-Cyrl");
         // German and Luxembourgish or Swiss German
       case "de-Latn":
         return reference.equals("lb-Latn") || reference.equals("gsw-Latn");
@@ -469,7 +480,7 @@ private static List<RelatedReferenceLocale> norwegian() {
         // Norwegian
         rrl("no", SAME_OR_INTERCHANGEABLE),
         // Nynorsk
-        rrl("nn", LOW));
+        rrl("nn", SAME_OR_INTERCHANGEABLE));
   }
 
   private static List<RelatedReferenceLocale> serbian() {