diff --git a/ApplicationLibCode/ProjectDataModel/RimTimeAxisAnnotation.cpp b/ApplicationLibCode/ProjectDataModel/RimTimeAxisAnnotation.cpp
index b4dba4a080..1619418055 100644
--- a/ApplicationLibCode/ProjectDataModel/RimTimeAxisAnnotation.cpp
+++ b/ApplicationLibCode/ProjectDataModel/RimTimeAxisAnnotation.cpp
@@ -18,20 +18,14 @@
 
 #include "RimTimeAxisAnnotation.h"
 
+#include "RiaColorTools.h"
 #include "RiaPreferences.h"
 #include "RiaQDateTimeTools.h"
 #include "RiaTimeTTools.h"
 
-#include "RigEclipseCaseData.h"
-#include "RigEquil.h"
+#include "RimProject.h"
 
 #include "RiuGuiTheme.h"
-#include "RiuQwtPlotCurve.h"
-
-#include "RimEclipseCase.h"
-#include "RimPlot.h"
-#include "RimTools.h"
-#include "RimViewWindow.h"
 
 #include <QDateTime>
 
@@ -48,6 +42,8 @@ RimTimeAxisAnnotation::RimTimeAxisAnnotation()
     CAF_PDM_InitObject( "Time Axis Annotation", ":/LeftAxis16x16.png" );
 
     m_value.uiCapability()->setUiHidden( true );
+
+    CAF_PDM_InitField( &m_color, "Color", RiaColorTools::fromQColorTo3f( defaultColor( AnnotationType::LINE ) ), "Color" );
 }
 
 //--------------------------------------------------------------------------------------------------
@@ -96,19 +92,43 @@ void RimTimeAxisAnnotation::setTimeRange( time_t startTime, time_t endTime )
 //--------------------------------------------------------------------------------------------------
 ///
 //--------------------------------------------------------------------------------------------------
-QColor RimTimeAxisAnnotation::color() const
+QColor RimTimeAxisAnnotation::defaultColor( AnnotationType annotationType )
 {
-    if ( annotationType() == AnnotationType::LINE )
+    if ( annotationType == AnnotationType::LINE )
     {
         return RiuGuiTheme::getColorByVariableName( "secondaryColor" ); // QColor(255, 0, 0);
     }
-    else if ( annotationType() == RimPlotAxisAnnotation::AnnotationType::RANGE )
+    else if ( annotationType == RimPlotAxisAnnotation::AnnotationType::RANGE )
     {
         return RiuGuiTheme::getColorByVariableName( "primaryColor" ); // QColor( 0, 0, 255 );
     }
     return RiuGuiTheme::getColorByVariableName( "textColor" ); // QColor(0, 0, 100);
 }
 
+//--------------------------------------------------------------------------------------------------
+///
+//--------------------------------------------------------------------------------------------------
+void RimTimeAxisAnnotation::setDefaultColor()
+{
+    m_color = RiaColorTools::fromQColorTo3f( defaultColor( annotationType() ) );
+}
+
+//--------------------------------------------------------------------------------------------------
+///
+//--------------------------------------------------------------------------------------------------
+void RimTimeAxisAnnotation::setColor( const cvf::Color3f& color )
+{
+    m_color = color;
+}
+
+//--------------------------------------------------------------------------------------------------
+///
+//--------------------------------------------------------------------------------------------------
+QColor RimTimeAxisAnnotation::color() const
+{
+    return RiaColorTools::toQColor( m_color );
+}
+
 //--------------------------------------------------------------------------------------------------
 ///
 //--------------------------------------------------------------------------------------------------
@@ -121,3 +141,14 @@ void RimTimeAxisAnnotation::defineUiOrdering( QString uiConfigName, caf::PdmUiOr
 
     uiOrdering.skipRemainingFields();
 }
+
+//--------------------------------------------------------------------------------------------------
+///
+//--------------------------------------------------------------------------------------------------
+void RimTimeAxisAnnotation::initAfterRead()
+{
+    if ( RimProject::current()->isProjectFileVersionEqualOrOlderThan( "2023.03" ) )
+    {
+        setDefaultColor();
+    }
+}
diff --git a/ApplicationLibCode/ProjectDataModel/RimTimeAxisAnnotation.h b/ApplicationLibCode/ProjectDataModel/RimTimeAxisAnnotation.h
index b6315d51ed..e369f90b29 100644
--- a/ApplicationLibCode/ProjectDataModel/RimTimeAxisAnnotation.h
+++ b/ApplicationLibCode/ProjectDataModel/RimTimeAxisAnnotation.h
@@ -25,6 +25,8 @@
 #include "cafPdmObject.h"
 #include "cafPdmPtrField.h"
 
+#include "cvfColor3.h"
+
 #include <QString>
 
 //==================================================================================================
@@ -42,6 +44,14 @@ public:
     void   setTimeRange( time_t startTime, time_t endTime );
     QColor color() const override;
 
+    void setColor( const cvf::Color3f& color );
+    void setDefaultColor();
+
 protected:
     void defineUiOrdering( QString uiConfigName, caf::PdmUiOrdering& uiOrdering ) override;
+    void initAfterRead() override;
+
+    static QColor defaultColor( AnnotationType annotationType );
+
+    caf::PdmField<cvf::Color3f> m_color;
 };
diff --git a/ApplicationLibCode/ProjectDataModel/Summary/RimSummaryDeclineCurve.cpp b/ApplicationLibCode/ProjectDataModel/Summary/RimSummaryDeclineCurve.cpp
index 2a2ee603e9..63f68edd91 100644
--- a/ApplicationLibCode/ProjectDataModel/Summary/RimSummaryDeclineCurve.cpp
+++ b/ApplicationLibCode/ProjectDataModel/Summary/RimSummaryDeclineCurve.cpp
@@ -423,6 +423,7 @@ void RimSummaryDeclineCurve::updateTimeAnnotations()
     if ( m_showTimeSelectionInPlot )
     {
         m_timeRangeAnnotation = plot->addTimeRangeAnnotation( m_minTimeStep, m_maxTimeStep );
+        m_timeRangeAnnotation->setColor( color() );
     }
 }
 
diff --git a/ApplicationLibCode/ProjectDataModel/Summary/RimSummaryPlot.cpp b/ApplicationLibCode/ProjectDataModel/Summary/RimSummaryPlot.cpp
index 6552582e31..3ca83e40a9 100644
--- a/ApplicationLibCode/ProjectDataModel/Summary/RimSummaryPlot.cpp
+++ b/ApplicationLibCode/ProjectDataModel/Summary/RimSummaryPlot.cpp
@@ -1351,6 +1351,7 @@ RimTimeAxisAnnotation* RimSummaryPlot::addTimeAnnotation( time_t time )
 
     auto* annotation = new RimTimeAxisAnnotation;
     annotation->setTime( time );
+    annotation->setDefaultColor();
 
     axisProps->appendAnnotation( annotation );
     return annotation;
@@ -1365,6 +1366,7 @@ RimTimeAxisAnnotation* RimSummaryPlot::addTimeRangeAnnotation( time_t startTime,
 
     auto* annotation = new RimTimeAxisAnnotation;
     annotation->setTimeRange( startTime, endTime );
+    annotation->setDefaultColor();
 
     axisProps->appendAnnotation( annotation );
     return annotation;
diff --git a/ApplicationLibCode/ProjectDataModel/Summary/RimSummaryRegressionAnalysisCurve.cpp b/ApplicationLibCode/ProjectDataModel/Summary/RimSummaryRegressionAnalysisCurve.cpp
index d9775debe4..1d877837a7 100644
--- a/ApplicationLibCode/ProjectDataModel/Summary/RimSummaryRegressionAnalysisCurve.cpp
+++ b/ApplicationLibCode/ProjectDataModel/Summary/RimSummaryRegressionAnalysisCurve.cpp
@@ -569,6 +569,7 @@ void RimSummaryRegressionAnalysisCurve::updateTimeAnnotations()
     if ( m_showTimeSelectionInPlot )
     {
         m_timeRangeAnnotation = plot->addTimeRangeAnnotation( m_minTimeStep, m_maxTimeStep );
+        m_timeRangeAnnotation->setColor( color() );
     }
 }