npgsql
diff --git a/‎src/Npgsql.NodaTime/Internal/PeriodConverter.cs
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+18-8Lines changed: 18 additions & 8 deletions b/‎src/Npgsql.NodaTime/Internal/PeriodConverter.cs
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+18-8Lines changed: 18 additions & 8 deletions
diff --git a/‎src/Npgsql.NodaTime/Properties/NpgsqlNodaTimeStrings.Designer.cs
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+41-12Lines changed: 41 additions & 12 deletions b/‎src/Npgsql.NodaTime/Properties/NpgsqlNodaTimeStrings.Designer.cs
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+41-12Lines changed: 41 additions & 12 deletions
diff --git a/‎src/Npgsql.NodaTime/Properties/NpgsqlNodaTimeStrings.resx
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+3Lines changed: 3 additions & 0 deletions b/‎src/Npgsql.NodaTime/Properties/NpgsqlNodaTimeStrings.resx
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diff --git a/‎test/Npgsql.PluginTests/NodaTimeTests.cs
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+12Lines changed: 12 additions & 0 deletions b/‎test/Npgsql.PluginTests/NodaTimeTests.cs
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+12Lines changed: 12 additions & 0 deletions
@@ -35,14 +35,24 @@ protected override void WriteCore(PgWriter writer, Period value)
     {
         // We have to normalize the value as otherwise we might get a value with 0 everything except for ticks, which we ignore
         value = value.Normalize();
-        // Note that the end result must be long
-        // see #3438
-        var microsecondsInDay =
-            (((value.Hours * NodaConstants.MinutesPerHour + value.Minutes) * NodaConstants.SecondsPerMinute + value.Seconds) * NodaConstants.MillisecondsPerSecond + value.Milliseconds) * 1000 +
-            value.Nanoseconds / 1000; // Take the microseconds, discard the nanosecond remainder
 
-        writer.WriteInt64(microsecondsInDay);
-        writer.WriteInt32(value.Weeks * 7 + value.Days); // days
-        writer.WriteInt32(value.Years * 12 + value.Months); // months
+        try
+        {
+            checked
+            {
+                // Note that the end result must be long
+                // see #3438
+                var microsecondsInDay =
+                    (((value.Hours * NodaConstants.MinutesPerHour + value.Minutes) * NodaConstants.SecondsPerMinute + value.Seconds) * NodaConstants.MillisecondsPerSecond + value.Milliseconds) * 1000 +
+                    value.Nanoseconds / 1000; // Take the microseconds, discard the nanosecond remainder
+                writer.WriteInt64(microsecondsInDay);
+                writer.WriteInt32(value.Weeks * 7 + value.Days); // days
+                writer.WriteInt32(value.Years * 12 + value.Months); // months
+            }
+        }
+        catch (OverflowException ex)
+        {
+            throw new ArgumentException(NpgsqlNodaTimeStrings.CannotWritePeriodDueToOverflow, ex);
+        }
     }
 }
@@ -24,4 +24,7 @@
     <data name="CannotReadIntervalWithMonthsAsDuration" xml:space="preserve">
         <value>Cannot read PostgreSQL interval with non-zero months to NodaTime Duration. Try reading as a NodaTime Period instead.</value>
     </data>
+    <data name="CannotWritePeriodDueToOverflow" xml:space="preserve">
+        <value>Cannot write NodaTime's Period because it's out of range for the PG interval type.</value>
+    </data>
 </root>
@@ -799,6 +799,18 @@ public async Task Normalize_period_on_write()
         Assert.That(dbValue, Is.EqualTo(expectedAfterRoundtrip));
     }
 
+    [Test]
+    public async Task Period_write_throw_on_overflow()
+    {
+        var periodBuilder = new PeriodBuilder
+        {
+            Years = int.MaxValue
+        };
+        var ex = await AssertTypeUnsupportedWrite<Period, ArgumentException>(periodBuilder.Build(), "interval");
+        Assert.That(ex.Message, Is.EqualTo(NpgsqlNodaTimeStrings.CannotWritePeriodDueToOverflow));
+        Assert.That(ex.InnerException, Is.TypeOf<OverflowException>());
+    }
+
     #endregion Interval
 
     #region Support