diff --git a/pandas/_libs/parsers.pyx b/pandas/_libs/parsers.pyx
index 8b9842ba087a5..aed1ee1c6f6e5 100644
--- a/pandas/_libs/parsers.pyx
+++ b/pandas/_libs/parsers.pyx
@@ -638,18 +638,19 @@ cdef class TextReader:
 
                 elif len(zip_names) == 0:
                     raise ValueError('Zero files found in compressed '
-                                     'zip file %s', source)
+                                     'zip file {source}'.format(source=source))
                 else:
                     raise ValueError('Multiple files found in compressed '
-                                     'zip file %s', str(zip_names))
+                                     'zip file {zip_names}'
+                                     .format(zip_names=str(zip_names)))
             elif self.compression == 'xz':
                 if isinstance(source, str):
                     source = _get_lzma_file(lzma)(source, 'rb')
                 else:
                     source = _get_lzma_file(lzma)(filename=source)
             else:
-                raise ValueError('Unrecognized compression type: %s' %
-                                 self.compression)
+                raise ValueError('Unrecognized compression type: {compression_type}'
+                                 .format(compression_type=self.compression))
 
             if b'utf-16' in (self.encoding or b''):
                 # we need to read utf-16 through UTF8Recoder.
@@ -703,8 +704,10 @@ cdef class TextReader:
             self.parser.cb_io = &buffer_rd_bytes
             self.parser.cb_cleanup = &del_rd_source
         else:
-            raise IOError('Expected file path name or file-like object,'
-                          ' got %s type' % type(source))
+            raise IOError('Expected file path name or file-like object, '
+                          'got {source_type} type'
+                          .format(source_type=type(source))
+                          )
 
     cdef _get_header(self):
         # header is now a list of lists, so field_count should use header[0]
@@ -741,11 +744,12 @@ cdef class TextReader:
                           self.parser.lines < hr):
                     msg = self.orig_header
                     if isinstance(msg, list):
-                        msg = "[%s], len of %d," % (
-                            ','.join(str(m) for m in msg), len(msg))
+                        msg = "[{msg_lst}], len of {orig_header_len},".format(
+                           msg_lst=(','.join(str(m) for m in msg)),
+                           orig_msg_len=len(msg))
                     raise ParserError(
-                        'Passed header=%s but only %d lines in file'
-                        % (msg, self.parser.lines))
+                        'Passed header={msg} but only {line_count} lines in file'
+                        .format(msg=msg, line_count=self.parser.lines))
 
                 else:
                     field_count = self.parser.line_fields[hr]
@@ -779,7 +783,10 @@ cdef class TextReader:
                     if not self.has_mi_columns and self.mangle_dupe_cols:
                         while count > 0:
                             counts[name] = count + 1
-                            name = '%s.%d' % (name, count)
+                            name = '{name}.{count}'.format(
+                                name=name,
+                                count=count
+                            )
                             count = counts.get(name, 0)
 
                     if old_name == '':
@@ -990,7 +997,9 @@ cdef class TextReader:
     cdef _end_clock(self, what):
         if self.verbose:
             elapsed = time.time() - self.clocks.pop(-1)
-            print('%s took: %.2f ms' % (what, elapsed * 1000))
+            print('{what} took: {elapsed} ms'
+                  .format(what=what, elapsed=round(elapsed * 1000, 2))
+                 )
 
     def set_noconvert(self, i):
         self.noconvert.add(i)
@@ -1662,7 +1671,8 @@ cdef _to_fw_string(parser_t *parser, int64_t col, int64_t line_start,
         char *data
         ndarray result
 
-    result = np.empty(line_end - line_start, dtype='|S%d' % width)
+    result = np.empty(line_end - line_start,
+                      dtype='|S{width}'.format(width=width))
     data = <char*>result.data
 
     with nogil:
@@ -2176,8 +2186,9 @@ def _concatenate_chunks(list chunks):
     if warning_columns:
         warning_names = ','.join(warning_columns)
         warning_message = " ".join([
-            "Columns (%s) have mixed types." % warning_names,
+            "Columns {col_name} have mixed types."
             "Specify dtype option on import or set low_memory=False."
+            .format(col_name=warning_names)
           ])
         warnings.warn(warning_message, DtypeWarning, stacklevel=8)
     return result