diff --git a/opm/parser/eclipse/EclipseState/IOConfig/IOConfig.cpp b/opm/parser/eclipse/EclipseState/IOConfig/IOConfig.cpp
index 98be17dad..6c9a52386 100644
--- a/opm/parser/eclipse/EclipseState/IOConfig/IOConfig.cpp
+++ b/opm/parser/eclipse/EclipseState/IOConfig/IOConfig.cpp
@@ -114,8 +114,8 @@ namespace Opm {
                     write_restart_file = true;
                 } else {
                     std::vector<size_t>::const_iterator ci_start = timesteps.begin();
-                    int index = std::distance( ci_start, ci_timestep );
-                    if( (index % frequency) == 0) {
+                    int dist = std::distance( ci_start, ci_timestep ) + 1;
+                    if( ( (dist > 0) && ((dist % frequency) == 0) ) ) {
                         write_restart_file = true;
                     }
                  }
diff --git a/opm/parser/eclipse/EclipseState/IOConfig/tests/IOConfigTest.cpp b/opm/parser/eclipse/EclipseState/IOConfig/tests/IOConfigTest.cpp
index d48fc5c6a..e7ab403bb 100644
--- a/opm/parser/eclipse/EclipseState/IOConfig/tests/IOConfigTest.cpp
+++ b/opm/parser/eclipse/EclipseState/IOConfig/tests/IOConfigTest.cpp
@@ -172,10 +172,10 @@ BOOST_AUTO_TEST_CASE(IOConfigTest) {
     frequency     = 0;
     ioConfigPtr->handleRPTRSTBasic(schedule.getTimeMap(),timestep, basic, frequency);
 
-    /*Expected results: Write timestep for timestep 17, 20, 22, 23, 26*/
+    /*Expected results: Write timestep for timestep 20, 22, 23, 26*/
 
     for (size_t ts = 17; ts <= 26; ++ts) {
-        if ((17 == ts) || (20 == ts) || (22 == ts) || (23 == ts) || (26 == ts)) {
+        if ((20 == ts) || (22 == ts) || (23 == ts) || (26 == ts)) {
             BOOST_CHECK_EQUAL(true, ioConfigPtr->getWriteRestartFile(ts));
         } else {
             BOOST_CHECK_EQUAL(false, ioConfigPtr->getWriteRestartFile(ts));
@@ -202,10 +202,10 @@ BOOST_AUTO_TEST_CASE(IOConfigTest) {
     frequency     = 2;
     ioConfigPtr->handleRPTRSTBasic(schedule.getTimeMap(), timestep, basic, frequency);
 
-    //Expected results: Write timestep for 27, 32 and 36 (27, 30, 32, 33, 36 with frequency 2)
+    //Expected results: Write timestep for 32 and 36 (30, 32, 33, 36 with frequency 2)
 
     for (size_t ts = 27; ts <= 36; ++ts) {
-        if ((27 == ts) || (32 == ts) || (36 == ts)) {
+        if ((32 == ts) || (36 == ts)) {
             BOOST_CHECK_EQUAL(true, ioConfigPtr->getWriteRestartFile(ts));
         } else {
             BOOST_CHECK_EQUAL(false, ioConfigPtr->getWriteRestartFile(ts));
@@ -236,7 +236,7 @@ BOOST_AUTO_TEST_CASE(IOConfigTest) {
     //Expected results: Write timestep for timestep  38, 44 (38, 42, 44 with frequency 2)
 
     for (size_t ts = 37; ts <= 46; ++ts) {
-        if ((38 == ts) || (44 == ts)) {
+        if (42 == ts) {
             BOOST_CHECK_EQUAL(true, ioConfigPtr->getWriteRestartFile(ts));
         } else {
             BOOST_CHECK_EQUAL(false, ioConfigPtr->getWriteRestartFile(ts));
diff --git a/opm/parser/eclipse/EclipseState/Schedule/TimeMap.cpp b/opm/parser/eclipse/EclipseState/Schedule/TimeMap.cpp
index d3328ae68..7c53b5264 100644
--- a/opm/parser/eclipse/EclipseState/Schedule/TimeMap.cpp
+++ b/opm/parser/eclipse/EclipseState/Schedule/TimeMap.cpp
@@ -229,7 +229,7 @@ namespace Opm {
      void TimeMap::initFirstTimestepsMonths(std::vector<size_t>& timesteps, size_t from_timestep) const {
         timesteps.clear();
 
-        const boost::posix_time::ptime& ptime_prev = getStartTime(from_timestep-1);
+        const boost::posix_time::ptime& ptime_prev = getStartTime(from_timestep);
         boost::gregorian::date prev_date = ptime_prev.date();
 
         for (size_t timestepIndex = from_timestep; timestepIndex < m_timeList.size(); ++timestepIndex) {
@@ -248,7 +248,7 @@ namespace Opm {
     void TimeMap::initFirstTimestepsYears(std::vector<size_t>& timesteps, size_t from_timestep) const {
         timesteps.clear();
 
-        const boost::posix_time::ptime& ptime_prev = getStartTime(from_timestep-1);
+        const boost::posix_time::ptime& ptime_prev = getStartTime(from_timestep);
         boost::gregorian::date prev_date = ptime_prev.date();
 
         for (size_t timestepIndex = from_timestep; timestepIndex < m_timeList.size(); ++timestepIndex) {
diff --git a/opm/parser/eclipse/EclipseState/Schedule/tests/TimeMapTest.cpp b/opm/parser/eclipse/EclipseState/Schedule/tests/TimeMapTest.cpp
index 84cd9bc30..bca1ad14c 100644
--- a/opm/parser/eclipse/EclipseState/Schedule/tests/TimeMapTest.cpp
+++ b/opm/parser/eclipse/EclipseState/Schedule/tests/TimeMapTest.cpp
@@ -337,9 +337,9 @@ BOOST_AUTO_TEST_CASE(initTimestepsYearsAndMonths) {
 
     first_timestep_of_each_month.clear();
     tmap.initFirstTimestepsMonths(first_timestep_of_each_month, 6);
-    BOOST_CHECK_EQUAL(7, first_timestep_of_each_month.size());
-    int expected_results3[7] = {6,8,9,10,11,12,13};
-    BOOST_CHECK_EQUAL_COLLECTIONS(expected_results3, expected_results3+7, first_timestep_of_each_month.begin(), first_timestep_of_each_month.end());
+    BOOST_CHECK_EQUAL(6, first_timestep_of_each_month.size());
+    int expected_results3[6] = {8,9,10,11,12,13};
+    BOOST_CHECK_EQUAL_COLLECTIONS(expected_results3, expected_results3+6, first_timestep_of_each_month.begin(), first_timestep_of_each_month.end());
 
     std::vector<size_t> first_timestep_of_each_year;
     tmap.initFirstTimestepsYears(first_timestep_of_each_year);
@@ -349,6 +349,6 @@ BOOST_AUTO_TEST_CASE(initTimestepsYearsAndMonths) {
 
     first_timestep_of_each_year.clear();
     tmap.initFirstTimestepsYears(first_timestep_of_each_year, 13);
-    BOOST_CHECK_EQUAL(1, first_timestep_of_each_year.size());
+    BOOST_CHECK_EQUAL(0, first_timestep_of_each_year.size());
 }