diff --git a/autotest/test_gwf_multimvr.py b/autotest/test_gwf_multimvr.py
index 9fddf576be0..d015f4c9d77 100644
--- a/autotest/test_gwf_multimvr.py
+++ b/autotest/test_gwf_multimvr.py
@@ -837,7 +837,8 @@ def add_parent_sfr(gwf, gwfname, conns):
         print_flows=True,
         mover=True,
         pname="SFR-parent",
-        unit_conversion=86400.00,
+        length_conversion=1.0,
+        time_conversion=86400.0,
         boundnames=False,
         nreaches=len(conns),
         packagedata=pkdat,
@@ -857,7 +858,8 @@ def add_child_sfr(gwfc, gwfnamec):
         print_flows=True,
         mover=True,
         pname="SFR-child",
-        unit_conversion=86400.00,
+        length_conversion=1.0,
+        time_conversion=86400.0,
         boundnames=False,
         nreaches=len(connsc),
         packagedata=pkdatc,
diff --git a/autotest/test_gwf_npf03_sfr.py b/autotest/test_gwf_npf03_sfr.py
index d4490ea4146..9791de56e62 100644
--- a/autotest/test_gwf_npf03_sfr.py
+++ b/autotest/test_gwf_npf03_sfr.py
@@ -30,7 +30,8 @@
 hbndl = [12.0, 8.0]
 
 # sfr data
-unit_conv = 1.0
+len_conv = 1.0
+time_conv = 1.0
 slope = 1.2012012e-03
 width = 20.0
 bthick = 1.5
@@ -270,7 +271,8 @@ def build_model(idx, dir):
 
         sfr = flopy.mf6.ModflowGwfsfr(
             gwf,
-            unit_conversion=unit_conv,
+            length_conversion=len_conv,
+            time_conversion=time_conv,
             print_stage=True,
             print_flows=True,
             package_convergence_filerecord=cnvgpth,
diff --git a/autotest/test_gwf_sfr_evap.py b/autotest/test_gwf_sfr_evap.py
index 2e9646680bc..99110341908 100644
--- a/autotest/test_gwf_sfr_evap.py
+++ b/autotest/test_gwf_sfr_evap.py
@@ -265,7 +265,8 @@ def build_model(idx, dir):
         print_stage=True,
         print_flows=True,
         print_input=True,
-        unit_conversion=1.0 * 86400,
+        length_conversion=1.0,
+        time_conversion=86400.0,
         budget_filerecord=budpth,
         mover=False,
         nreaches=nreaches,
@@ -362,7 +363,8 @@ def build_model(idx, dir):
         print_stage=True,
         print_flows=True,
         print_input=True,
-        unit_conversion=1.0 * 86400,
+        length_conversion=1.0,
+        time_conversion=86400.0,
         budget_filerecord=budpth,
         mover=False,
         nreaches=nreaches,
diff --git a/autotest/test_gwf_vsc03_sfr.py b/autotest/test_gwf_vsc03_sfr.py
index 97e0148e148..b16860e5f8f 100644
--- a/autotest/test_gwf_vsc03_sfr.py
+++ b/autotest/test_gwf_vsc03_sfr.py
@@ -315,7 +315,8 @@ def build_model(idx, dir):
         print_flows=True,
         print_input=False,
         auxiliary=["VDUMMY", "TEMPERATURE"],
-        unit_conversion=1.486 * 86400,
+        length_conversion=3.28084,
+        time_conversion=86400.0,
         budget_filerecord=budpth,
         mover=False,
         nreaches=nreaches,
diff --git a/autotest/test_gwt_prudic2004t2.py b/autotest/test_gwt_prudic2004t2.py
index 6c052338a59..d52364d4ed8 100644
--- a/autotest/test_gwt_prudic2004t2.py
+++ b/autotest/test_gwt_prudic2004t2.py
@@ -211,7 +211,8 @@ def build_model(idx, dir):
             budget_filerecord=gwfname + ".sfr.bud",
             mover=True,
             pname="SFR-1",
-            unit_conversion=128390.00,
+            length_conversion=3.28084,
+            time_conversion=86400.0,
             boundnames=True,
             nreaches=len(rivlist),
             packagedata=sfrpackagedata,
diff --git a/autotest/test_gwt_prudic2004t2fmi.py b/autotest/test_gwt_prudic2004t2fmi.py
index 94378e064d0..328de6660b1 100644
--- a/autotest/test_gwt_prudic2004t2fmi.py
+++ b/autotest/test_gwt_prudic2004t2fmi.py
@@ -208,7 +208,8 @@ def run_flow_model(dir, exe):
             budget_filerecord=gwfname + ".sfr.bud",
             mover=True,
             pname="SFR-1",
-            unit_conversion=128390.00,
+            length_conversion=3.28084,
+            time_conversion=86400.0,
             boundnames=True,
             nreaches=len(rivlist),
             packagedata=sfrpackagedata,
diff --git a/autotest/test_gwt_prudic2004t2fmiats.py b/autotest/test_gwt_prudic2004t2fmiats.py
index 446aec445e8..a506d9344c0 100644
--- a/autotest/test_gwt_prudic2004t2fmiats.py
+++ b/autotest/test_gwt_prudic2004t2fmiats.py
@@ -212,7 +212,8 @@ def run_flow_model(dir, exe):
             budget_filerecord=gwfname + ".sfr.bud",
             mover=True,
             pname="SFR-1",
-            unit_conversion=128390.00,
+            length_conversion=3.28084,
+            time_conversion=86400.0,
             boundnames=True,
             nreaches=len(rivlist),
             packagedata=sfrpackagedata,
diff --git a/autotest/test_gwt_prudic2004t2gwtgwt.py b/autotest/test_gwt_prudic2004t2gwtgwt.py
index 71577f18af4..4d6a4da25a2 100644
--- a/autotest/test_gwt_prudic2004t2gwtgwt.py
+++ b/autotest/test_gwt_prudic2004t2gwtgwt.py
@@ -388,7 +388,8 @@ def build_gwfgwt_combo(
                 mover=True,
                 pname=f"SFR-{isfrseg}",
                 filename=f"{gwfname}.sfr{isfrseg}",
-                unit_conversion=128390.00,
+                length_conversion=3.28084,
+                time_conversion=86400.0,
                 boundnames=False,
                 nreaches=nreaches,
                 packagedata=sfrpd,
diff --git a/autotest/test_gwt_ssm06.py b/autotest/test_gwt_ssm06.py
index 1371aec43e2..97ebc465457 100644
--- a/autotest/test_gwt_ssm06.py
+++ b/autotest/test_gwt_ssm06.py
@@ -189,7 +189,8 @@ def run_flw_and_trnprt_models(dir, exe):
         budget_filerecord=gwfname + ".sfr.bud",
         save_flows=True,
         pname="SFR-1",
-        unit_conversion=86400.0 * 1.486,
+        length_conversion=3.28084,
+        time_conversion=86400.0,
         boundnames=False,
         nreaches=len(conns),
         packagedata=sfr_pkdat,
diff --git a/autotest/test_gwt_ssm06fmi.py b/autotest/test_gwt_ssm06fmi.py
index 372b1efd1d4..8f8dc8f142a 100644
--- a/autotest/test_gwt_ssm06fmi.py
+++ b/autotest/test_gwt_ssm06fmi.py
@@ -204,7 +204,8 @@ def run_flow_model(dir, exe):
         budget_filerecord=gwfname + ".sfr.bud",
         save_flows=True,
         pname="SFR-1",
-        unit_conversion=86400.0 * 1.486,
+        length_conversion=3.28084,
+        time_conversion=86400.0,
         boundnames=False,
         nreaches=len(conns),
         packagedata=sfr_pkdat,