diff --git a/jax/_src/api.py b/jax/_src/api.py
index ceea2a5a0d53..fc72059a30d6 100644
--- a/jax/_src/api.py
+++ b/jax/_src/api.py
@@ -3268,11 +3268,6 @@ def clear_backends():
   """
   Clear all backend clients so that new backend clients can be created later.
   """
-
-  if xc._version < 79:
-    raise RuntimeError("clear_backends is not supported in the jaxlib used."
-                       "Please update your jaxlib package.")
-
   xb._clear_backends()
   jax.lib.xla_bridge._backends = {}
   dispatch.xla_callable.cache_clear()  # type: ignore
diff --git a/jax/_src/distributed.py b/jax/_src/distributed.py
index 6f39364cbbc8..d4c96dd37d1e 100644
--- a/jax/_src/distributed.py
+++ b/jax/_src/distributed.py
@@ -22,7 +22,6 @@
 from jax._src import cloud_tpu_init
 from jax._src.config import config
 from jax._src.lib import xla_bridge
-from jax._src.lib import xla_client
 from jax._src.lib import xla_extension
 
 class State:
@@ -79,7 +78,7 @@ def initialize(self,
     logging.info('Connecting to JAX distributed service on %s', coordinator_address)
     self.client.connect()
 
-    if xla_client._version >= 77 and config.jax_coordination_service:
+    if config.jax_coordination_service:
       self.initialize_preemption_sync_manager()
 
   def shutdown(self):
diff --git a/jax/_src/lax/convolution.py b/jax/_src/lax/convolution.py
index 52a8024803bd..dc03a4602e32 100644
--- a/jax/_src/lax/convolution.py
+++ b/jax/_src/lax/convolution.py
@@ -19,7 +19,6 @@
 
 import numpy as np
 
-from jax._src.lib import mlir_api_version
 from jax import core
 from jax._src import dtypes
 from jax._src.lax import lax
@@ -704,23 +703,20 @@ def _conv_general_dilated_lower(
   if len(padding) == 0:
     padding = np.zeros((0, 2), dtype=np.int64)
   window_reversal = mlir.dense_bool_elements([False] * num_spatial_dims)
-  if mlir_api_version < 24:
-    op = mhlo.ConvOp
-  else:
-    op = mhlo.ConvolutionOp
   return [
-      op(mlir.aval_to_ir_type(aval_out),
-         lhs,
-         rhs,
-         dimension_numbers=dnums,
-         feature_group_count=mlir.i64_attr(feature_group_count),
-         batch_group_count=mlir.i64_attr(batch_group_count),
-         window_strides=mlir.dense_int_elements(window_strides),
-         padding=mlir.dense_int_elements(padding),
-         lhs_dilation=mlir.dense_int_elements(lhs_dilation),
-         rhs_dilation=mlir.dense_int_elements(rhs_dilation),
-         window_reversal=window_reversal,
-         precision_config=lax.precision_attr(precision)).result
+      mhlo.ConvolutionOp(
+        mlir.aval_to_ir_type(aval_out),
+        lhs,
+        rhs,
+        dimension_numbers=dnums,
+        feature_group_count=mlir.i64_attr(feature_group_count),
+        batch_group_count=mlir.i64_attr(batch_group_count),
+        window_strides=mlir.dense_int_elements(window_strides),
+        padding=mlir.dense_int_elements(padding),
+        lhs_dilation=mlir.dense_int_elements(lhs_dilation),
+        rhs_dilation=mlir.dense_int_elements(rhs_dilation),
+        window_reversal=window_reversal,
+        precision_config=lax.precision_attr(precision)).result
   ]
 
 mlir.register_lowering(conv_general_dilated_p, _conv_general_dilated_lower)
diff --git a/jax/_src/lax/lax.py b/jax/_src/lax/lax.py
index 6e9def67758a..aa433343aa9c 100644
--- a/jax/_src/lax/lax.py
+++ b/jax/_src/lax/lax.py
@@ -1755,17 +1755,11 @@ def logistic_impl(x):
 
 sin_p = standard_unop(_float | _complex, 'sin')
 ad.defjvp(sin_p, lambda g, x: mul(g, cos(x)))
-if mlir_api_version < 27:
-  mlir.register_lowering(sin_p, partial(_nary_lower_mhlo, mhlo.SinOp))
-else:
-  mlir.register_lowering(sin_p, partial(_nary_lower_mhlo, mhlo.SineOp))
+mlir.register_lowering(sin_p, partial(_nary_lower_mhlo, mhlo.SineOp))
 
 cos_p = standard_unop(_float | _complex, 'cos')
 ad.defjvp(cos_p, lambda g, x: neg(mul(g, sin(x))))
-if mlir_api_version < 28:
-  mlir.register_lowering(cos_p, partial(_nary_lower_mhlo, mhlo.CosOp))
-else:
-  mlir.register_lowering(cos_p, partial(_nary_lower_mhlo, mhlo.CosineOp))
+mlir.register_lowering(cos_p, partial(_nary_lower_mhlo, mhlo.CosineOp))
 
 @_upcast_fp16_for_computation
 def _tan_impl(x):
@@ -2170,10 +2164,7 @@ def _sub_transpose(t, x, y):
 sub_p = standard_naryop([_num, _num], 'sub')
 ad.primitive_jvps[sub_p] = _sub_jvp
 ad.primitive_transposes[sub_p] = _sub_transpose
-if mlir_api_version < 29:
-  mlir.register_lowering(sub_p, partial(_nary_lower_mhlo, mhlo.SubOp))
-else:
-  mlir.register_lowering(sub_p, partial(_nary_lower_mhlo, mhlo.SubtractOp))
+mlir.register_lowering(sub_p, partial(_nary_lower_mhlo, mhlo.SubtractOp))
 
 
 def _mul_transpose(ct, x, y):
@@ -4244,11 +4235,8 @@ def _rng_uniform_lowering(ctx, a, b, *, shape):
   aval_out, = ctx.avals_out
   shape, = mlir.ir_constants(np.array(aval_out.shape, np.int64),
                              canonicalize_types=False)
-  if mlir_api_version <= 22:
-    return mhlo.RngUniformOp(a, b, shape).results
-  else:
-    return mhlo.RngOp(a, b, shape,
-                      mhlo.RngDistributionAttr.get('UNIFORM')).results
+  return mhlo.RngOp(a, b, shape,
+                    mhlo.RngDistributionAttr.get('UNIFORM')).results
 
 mlir.register_lowering(rng_uniform_p, _rng_uniform_lowering)
 
diff --git a/jax/_src/lax/linalg.py b/jax/_src/lax/linalg.py
index 7bd023ebe3df..2555ad2095f5 100644
--- a/jax/_src/lax/linalg.py
+++ b/jax/_src/lax/linalg.py
@@ -39,7 +39,6 @@
 from jax._src.lax import eigh as lax_eigh
 from jax._src.lax import lax as lax_internal
 from jax._src.lax import svd as lax_svd
-from jax._src.lib import mlir_api_version
 from jax._src.lib import lapack
 
 from jax._src.lib import gpu_linalg
@@ -1189,11 +1188,7 @@ def _lu_cpu_gpu_lowering(getrf_impl, ctx, operand):
   m = operand_aval.shape[-2]
   lu, pivot, info = getrf_impl(operand_aval.dtype, operand)
   # Subtract 1 from the pivot to get 0-based indices.
-  if mlir_api_version < 29:
-    op = mhlo.SubOp
-  else:
-    op = mhlo.SubtractOp
-  pivot = op(pivot, mlir.full_like_aval(1, pivot_aval)).result
+  pivot = mhlo.SubtractOp(pivot, mlir.full_like_aval(1, pivot_aval)).result
   ok = mlir.compare_mhlo(
       info, mlir.full_like_aval(0, ShapedArray(batch_dims, np.dtype(np.int32))),
       "GE", "SIGNED")
diff --git a/jax/_src/lib/mlir/dialects/__init__.py b/jax/_src/lib/mlir/dialects/__init__.py
index 4b53dedde9c9..81d892a24d58 100644
--- a/jax/_src/lib/mlir/dialects/__init__.py
+++ b/jax/_src/lib/mlir/dialects/__init__.py
@@ -17,18 +17,5 @@
 import jaxlib.mlir.dialects.chlo as chlo
 import jaxlib.mlir.dialects.mhlo as mhlo
 import jaxlib.mlir.dialects.func as func
-
-try:
-  import jaxlib.mlir.dialects.ml_program as ml_program
-except (ModuleNotFoundError, ImportError):
-  # TODO(phawkins): make this unconditional when jaxlib > 0.3.14
-  #                        is the minimum version.
-  pass
-
-try:
-  import jaxlib.mlir.dialects.sparse_tensor as sparse_tensor
-except (ModuleNotFoundError, ImportError):
-  # TODO(ajcbik,phawkins): make this unconditional when jaxlib > 0.3.7
-  #                        is the minimum version.
-  pass
-
+import jaxlib.mlir.dialects.ml_program as ml_program
+import jaxlib.mlir.dialects.sparse_tensor as sparse_tensor
diff --git a/jax/_src/lib/xla_bridge.py b/jax/_src/lib/xla_bridge.py
index 4f94aad8f582..38e648296550 100644
--- a/jax/_src/lib/xla_bridge.py
+++ b/jax/_src/lib/xla_bridge.py
@@ -162,8 +162,7 @@ def get_compile_options(
     debug_options.xla_llvm_disable_expensive_passes = True
     debug_options.xla_test_all_input_layouts = False
 
-  if lib.xla_extension_version >= 68:
-    compile_options.profile_version = FLAGS.jax_xla_profile_version
+  compile_options.profile_version = FLAGS.jax_xla_profile_version
   return compile_options
 
 
diff --git a/jax/_src/tree_util.py b/jax/_src/tree_util.py
index d90257e1f983..3d7e259df34a 100644
--- a/jax/_src/tree_util.py
+++ b/jax/_src/tree_util.py
@@ -23,8 +23,6 @@
 import warnings
 
 from jax._src.lib import pytree
-from jax._src.lib import xla_extension
-from jax._src.lib import xla_extension_version
 
 from jax._src.util import safe_zip, unzip2
 
@@ -34,10 +32,7 @@
 T = TypeVar("T")
 U = TypeVar("U")
 
-if TYPE_CHECKING or xla_extension_version >= 78:
-  PyTreeDef = pytree.PyTreeDef
-else:
-  PyTreeDef = xla_extension.PyTreeDef  # pytype: disable=module-attr
+PyTreeDef = pytree.PyTreeDef
 
 
 def tree_flatten(tree, is_leaf: Optional[Callable[[Any], bool]] = None):
diff --git a/jax/version.py b/jax/version.py
index f79264cb068e..4769e008e9ca 100644
--- a/jax/version.py
+++ b/jax/version.py
@@ -16,7 +16,7 @@
 # eval()-ed by setup.py, so it should not have any dependencies.
 
 __version__ = "0.3.18"
-_minimum_jaxlib_version = "0.3.14"
+_minimum_jaxlib_version = "0.3.15"
 
 def _version_as_tuple(version_str):
   return tuple(int(i) for i in version_str.split(".") if i.isdigit())
diff --git a/tests/clear_backends_test.py b/tests/clear_backends_test.py
index 66639f10b77e..446b790b75ec 100644
--- a/tests/clear_backends_test.py
+++ b/tests/clear_backends_test.py
@@ -19,7 +19,6 @@
 from jax.config import config
 from jax._src import test_util as jtu
 from jax._src.lib import xla_bridge as xb
-from jax._src.lib import xla_client as xc
 
 config.parse_flags_with_absl()
 
@@ -29,11 +28,10 @@ class ClearBackendsTest(jtu.JaxTestCase):
   def test_clear_backends(self):
     g = jax.jit(lambda x, y: x * y)
     self.assertEqual(g(1, 2), 2)
-    if xc._version >= 79:
-      self.assertNotEmpty(xb.get_backend().live_executables())
-      jax.clear_backends()
-      self.assertEmpty(xb.get_backend().live_executables())
-      self.assertEqual(g(1, 2), 2)
+    self.assertNotEmpty(xb.get_backend().live_executables())
+    jax.clear_backends()
+    self.assertEmpty(xb.get_backend().live_executables())
+    self.assertEqual(g(1, 2), 2)
 
 
 if __name__ == "__main__":