diff --git a/src/fuel_efficiency.cpp b/src/fuel_efficiency.cpp
--- a/src/fuel_efficiency.cpp
+++ b/src/fuel_efficiency.cpp
@@ -90,7 +90,7 @@
                                                  i18nc("fuelefficiency unit symbol", "mpg (imperial)"),
                                                  i18nc("unit description in lists", "miles per imperial gallon"),
                                                  i18nc("unit synonyms for matching user input",
-                                                       "mile per imperial gallon;miles per imperial gallon;mpg (imperial)"),
+                                                       "mile per imperial gallon;miles per imperial gallon;mpg (imperial);imp mpg;mpg (imp)"),
                                                  symbolString,
                                                  ki18nc("amount in units (real)", "%1 miles per imperial gallon"),
                                                  ki18ncp("amount in units (integer)", "%1 mile per imperial gallon",
diff --git a/src/unit.h b/src/unit.h
--- a/src/unit.h
+++ b/src/unit.h
@@ -97,6 +97,8 @@
     FluidOunce, Cup, GallonUS, PintImperial,
     /** @since 5.53 */
     OilBarrel,
+    /** @since 5.70 */
+    GallonImperial, PintUS,
 
     // Mass
     Yottagram = 4000, Zettagram, Exagram, Petagram, Teragram, Gigagram, Megagram, Kilogram,
diff --git a/src/volume.cpp b/src/volume.cpp
--- a/src/volume.cpp
+++ b/src/volume.cpp
@@ -440,6 +440,15 @@
                              ki18nc("amount in units (real)", "%1 gallons (U.S. liquid)"),
                              ki18ncp("amount in units (integer)", "%1 gallon (U.S. liquid)", "%1 gallons (U.S. liquid)")));
 
+    addUnit(CustomUnit(VolumeCategory, GallonImperial, 0.00454609,
+                       i18nc("volume unit symbol", "imp gal"),
+                       i18nc("unit description in lists", "gallons (imperial)"),
+                       i18nc("unit synonyms for matching user input",
+                             "gallon (imperial);gallons (imperial);imp gal;imp gallon;imp gallons;imperial gal;imperial gallon;imperial gallons"),
+                       symbolString,
+                       ki18nc("amount in units (real)", "%1 gallons (imperial)"),
+                       ki18ncp("amount in units (integer)", "%1 gallon (imperial)", "%1 gallons (imperial)")));
+
     addCommonUnit(CustomUnit(VolumeCategory, PintImperial, 0.000568261,
                              i18nc("volume unit symbol", "pt"),
                              i18nc("unit description in lists", "pints (imperial)"),
@@ -449,6 +458,15 @@
                              ki18nc("amount in units (real)", "%1 pints (imperial)"),
                              ki18ncp("amount in units (integer)", "%1 pint (imperial)", "%1 pints (imperial)")));
 
+    addUnit(CustomUnit(VolumeCategory, PintUS, 0.000473176,
+                       i18nc("volume unit symbol", "US pt"),
+                       i18nc("unit description in lists", "pints (U.S. liquid)"),
+                       i18nc("unit synonyms for matching user input",
+                             "pint (U.S. liquid);pints (U.S. liquid);US pt;US pint;US pints;US p"),
+                       symbolString,
+                       ki18nc("amount in units (real)", "%1 pints (U.S. liquid)"),
+                       ki18ncp("amount in units (integer)", "%1 pint (U.S. liquid)", "%1 pints (U.S. liquid)")));
+
      addUnit(CustomUnit(VolumeCategory, OilBarrel, 0.158987294,
                              i18nc("volume unit symbol", "bbl"),
                              i18nc("unit description in lists", "oil barrels"),