diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/collectionOperations.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/collectionOperations.scala
index b32e9ee05f1ef..026a2a677baec 100644
--- a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/collectionOperations.scala
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/collectionOperations.scala
@@ -2628,7 +2628,7 @@ object Sequence {
         val maxEstimatedArrayLength =
           getSequenceLength(startMicros, stopMicros, intervalStepInMicros)
 
-        val stepSign = if (stopMicros > startMicros) +1 else -1
+        val stepSign = if (stopMicros >= startMicros) +1 else -1
         val exclusiveItem = stopMicros + stepSign
         val arr = new Array[T](maxEstimatedArrayLength)
         var t = startMicros
@@ -2690,7 +2690,7 @@ object Sequence {
          |
          |  $sequenceLengthCode
          |
-         |  final int $stepSign = $stopMicros > $startMicros ? +1 : -1;
+         |  final int $stepSign = $stopMicros >= $startMicros ? +1 : -1;
          |  final long $exclusiveItem = $stopMicros + $stepSign;
          |
          |  $arr = new $elemType[$arrLength];
diff --git a/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/expressions/CollectionExpressionsSuite.scala b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/expressions/CollectionExpressionsSuite.scala
index a4baad0c72444..3a0c02b29d92c 100644
--- a/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/expressions/CollectionExpressionsSuite.scala
+++ b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/expressions/CollectionExpressionsSuite.scala
@@ -1836,4 +1836,22 @@ class CollectionExpressionsSuite extends SparkFunSuite with ExpressionEvalHelper
     checkEvaluation(ArrayIntersect(empty, oneNull), Seq.empty)
     checkEvaluation(ArrayIntersect(oneNull, empty), Seq.empty)
   }
+
+  test("SPARK-31980: Start and end equal in month range") {
+    checkEvaluation(new Sequence(
+      Literal(Date.valueOf("2018-01-01")),
+      Literal(Date.valueOf("2018-01-01")),
+      Literal(stringToInterval("interval 1 day"))),
+      Seq(Date.valueOf("2018-01-01")))
+    checkEvaluation(new Sequence(
+      Literal(Date.valueOf("2018-01-01")),
+      Literal(Date.valueOf("2018-01-01")),
+      Literal(stringToInterval("interval 1 month"))),
+      Seq(Date.valueOf("2018-01-01")))
+    checkEvaluation(new Sequence(
+      Literal(Date.valueOf("2018-01-01")),
+      Literal(Date.valueOf("2018-01-01")),
+      Literal(stringToInterval("interval 1 year"))),
+      Seq(Date.valueOf("2018-01-01")))
+  }
 }