diff --git a/x-pack/plugin/esql-core/src/main/java/org/elasticsearch/xpack/esql/core/type/DataType.java b/x-pack/plugin/esql-core/src/main/java/org/elasticsearch/xpack/esql/core/type/DataType.java
index f59af4a1282cc..f7f9d238ec5ce 100644
--- a/x-pack/plugin/esql-core/src/main/java/org/elasticsearch/xpack/esql/core/type/DataType.java
+++ b/x-pack/plugin/esql-core/src/main/java/org/elasticsearch/xpack/esql/core/type/DataType.java
@@ -229,25 +229,10 @@ public static boolean isNullOrNumeric(DataType t) {
         return t.isNumeric() || isNull(t);
     }
 
-    public static boolean isSigned(DataType t) {
-        return t.isNumeric() && t.equals(UNSIGNED_LONG) == false;
-    }
-
     public static boolean isDateTime(DataType type) {
         return type == DATETIME;
     }
 
-    public static boolean areCompatible(DataType left, DataType right) {
-        if (left == right) {
-            return true;
-        } else {
-            return (left == NULL || right == NULL)
-                || (isString(left) && isString(right))
-                || (left.isNumeric() && right.isNumeric())
-                || (isDateTime(left) && isDateTime(right));
-        }
-    }
-
     public String nameUpper() {
         return name;
     }
diff --git a/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/Column.java b/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/Column.java
index a19dafba1559b..6287bf54ce5b0 100644
--- a/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/Column.java
+++ b/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/Column.java
@@ -15,7 +15,6 @@
 import org.elasticsearch.core.Releasables;
 import org.elasticsearch.xpack.esql.core.type.DataType;
 import org.elasticsearch.xpack.esql.planner.PlannerUtils;
-import org.elasticsearch.xpack.esql.type.EsqlDataTypes;
 
 import java.io.IOException;
 
@@ -28,7 +27,7 @@ public record Column(DataType type, Block values) implements Releasable, Writeab
     }
 
     public Column(BlockStreamInput in) throws IOException {
-        this(EsqlDataTypes.fromTypeName(in.readString()), in.readNamedWriteable(Block.class));
+        this(DataType.fromTypeName(in.readString()), in.readNamedWriteable(Block.class));
     }
 
     @Override
diff --git a/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/analysis/Verifier.java b/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/analysis/Verifier.java
index a4e0d99b0d3fc..4dfdb107e5bac 100644
--- a/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/analysis/Verifier.java
+++ b/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/analysis/Verifier.java
@@ -343,7 +343,7 @@ private static void checkRegexExtractOnlyOnStrings(LogicalPlan p, Set<Failure> f
         if (p instanceof RegexExtract re) {
             Expression expr = re.input();
             DataType type = expr.dataType();
-            if (EsqlDataTypes.isString(type) == false) {
+            if (DataType.isString(type) == false) {
                 failures.add(
                     fail(
                         expr,
diff --git a/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/enrich/EnrichLookupService.java b/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/enrich/EnrichLookupService.java
index 2425fa24b17c2..0f80fb809fa0b 100644
--- a/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/enrich/EnrichLookupService.java
+++ b/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/enrich/EnrichLookupService.java
@@ -83,7 +83,6 @@
 import org.elasticsearch.xpack.esql.planner.EsPhysicalOperationProviders;
 import org.elasticsearch.xpack.esql.planner.PlannerUtils;
 import org.elasticsearch.xpack.esql.plugin.EsqlPlugin;
-import org.elasticsearch.xpack.esql.type.EsqlDataTypes;
 
 import java.io.IOException;
 import java.util.ArrayList;
@@ -467,7 +466,7 @@ private static class LookupRequest extends TransportRequest implements IndicesRe
             String inputDataType = (in.getTransportVersion().onOrAfter(TransportVersions.ESQL_EXTENDED_ENRICH_INPUT_TYPE))
                 ? in.readString()
                 : "unknown";
-            this.inputDataType = EsqlDataTypes.fromTypeName(inputDataType);
+            this.inputDataType = DataType.fromTypeName(inputDataType);
             this.matchType = in.readString();
             this.matchField = in.readString();
             try (BlockStreamInput bsi = new BlockStreamInput(in, blockFactory)) {
diff --git a/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/enrich/EnrichPolicyResolver.java b/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/enrich/EnrichPolicyResolver.java
index 82eda9679074d..2d42241d77ada 100644
--- a/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/enrich/EnrichPolicyResolver.java
+++ b/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/enrich/EnrichPolicyResolver.java
@@ -37,11 +37,11 @@
 import org.elasticsearch.xpack.core.enrich.EnrichPolicy;
 import org.elasticsearch.xpack.esql.analysis.EnrichResolution;
 import org.elasticsearch.xpack.esql.core.index.EsIndex;
+import org.elasticsearch.xpack.esql.core.type.DataType;
 import org.elasticsearch.xpack.esql.core.type.EsField;
 import org.elasticsearch.xpack.esql.core.util.StringUtils;
 import org.elasticsearch.xpack.esql.plan.logical.Enrich;
 import org.elasticsearch.xpack.esql.session.IndexResolver;
-import org.elasticsearch.xpack.esql.type.EsqlDataTypes;
 
 import java.io.IOException;
 import java.util.ArrayList;
@@ -192,7 +192,7 @@ private Tuple<ResolvedEnrichPolicy, String> mergeLookupResults(
                 EsField field = m.getValue();
                 field = new EsField(
                     field.getName(),
-                    EsqlDataTypes.fromTypeName(field.getDataType().typeName()),
+                    DataType.fromTypeName(field.getDataType().typeName()),
                     field.getProperties(),
                     field.isAggregatable(),
                     field.isAlias()
diff --git a/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/convert/AbstractConvertFunction.java b/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/convert/AbstractConvertFunction.java
index 0fed02f89fd92..b731a400deba3 100644
--- a/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/convert/AbstractConvertFunction.java
+++ b/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/convert/AbstractConvertFunction.java
@@ -26,7 +26,6 @@
 import org.elasticsearch.xpack.esql.expression.function.Warnings;
 import org.elasticsearch.xpack.esql.expression.function.scalar.UnaryScalarFunction;
 import org.elasticsearch.xpack.esql.io.stream.PlanStreamInput;
-import org.elasticsearch.xpack.esql.type.EsqlDataTypes;
 
 import java.io.IOException;
 import java.util.ArrayList;
@@ -50,7 +49,7 @@ public abstract class AbstractConvertFunction extends UnaryScalarFunction {
 
     // the numeric types convert functions need to handle; the other numeric types are converted upstream to one of these
     private static final List<DataType> NUMERIC_TYPES = List.of(DataType.INTEGER, DataType.LONG, DataType.UNSIGNED_LONG, DataType.DOUBLE);
-    public static final List<DataType> STRING_TYPES = DataType.types().stream().filter(EsqlDataTypes::isString).toList();
+    public static final List<DataType> STRING_TYPES = DataType.types().stream().filter(DataType::isString).toList();
 
     protected AbstractConvertFunction(Source source, Expression field) {
         super(source, field);
diff --git a/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/date/DateExtract.java b/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/date/DateExtract.java
index 5a57e98be38b9..f9dcdeb342cb5 100644
--- a/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/date/DateExtract.java
+++ b/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/date/DateExtract.java
@@ -26,7 +26,6 @@
 import org.elasticsearch.xpack.esql.expression.function.Param;
 import org.elasticsearch.xpack.esql.expression.function.scalar.EsqlConfigurationFunction;
 import org.elasticsearch.xpack.esql.io.stream.PlanStreamInput;
-import org.elasticsearch.xpack.esql.type.EsqlDataTypes;
 
 import java.io.IOException;
 import java.time.ZoneId;
@@ -129,7 +128,7 @@ private ChronoField chronoField() {
         if (chronoField == null) {
             Expression field = children().get(0);
             try {
-                if (field.foldable() && EsqlDataTypes.isString(field.dataType())) {
+                if (field.foldable() && DataType.isString(field.dataType())) {
                     chronoField = (ChronoField) STRING_TO_CHRONO_FIELD.convert(field.fold());
                 }
             } catch (Exception e) {
diff --git a/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/date/DateFormat.java b/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/date/DateFormat.java
index 84a1a6e77ea73..bfc1bbaa5101d 100644
--- a/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/date/DateFormat.java
+++ b/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/date/DateFormat.java
@@ -27,7 +27,6 @@
 import org.elasticsearch.xpack.esql.expression.function.scalar.EsqlConfigurationFunction;
 import org.elasticsearch.xpack.esql.io.stream.PlanStreamInput;
 import org.elasticsearch.xpack.esql.session.EsqlConfiguration;
-import org.elasticsearch.xpack.esql.type.EsqlDataTypes;
 
 import java.io.IOException;
 import java.util.List;
@@ -146,7 +145,7 @@ public ExpressionEvaluator.Factory toEvaluator(Function<Expression, ExpressionEv
         if (format == null) {
             return new DateFormatConstantEvaluator.Factory(source(), fieldEvaluator, DEFAULT_DATE_TIME_FORMATTER);
         }
-        if (EsqlDataTypes.isString(format.dataType()) == false) {
+        if (DataType.isString(format.dataType()) == false) {
             throw new IllegalArgumentException("unsupported data type for format [" + format.dataType() + "]");
         }
         if (format.foldable()) {
diff --git a/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/date/DateParse.java b/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/date/DateParse.java
index eb710e72882b1..27b613e0e6d5a 100644
--- a/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/date/DateParse.java
+++ b/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/scalar/date/DateParse.java
@@ -26,7 +26,6 @@
 import org.elasticsearch.xpack.esql.expression.function.Param;
 import org.elasticsearch.xpack.esql.expression.function.scalar.EsqlScalarFunction;
 import org.elasticsearch.xpack.esql.io.stream.PlanStreamInput;
-import org.elasticsearch.xpack.esql.type.EsqlDataTypes;
 
 import java.io.IOException;
 import java.time.ZoneId;
@@ -143,7 +142,7 @@ public ExpressionEvaluator.Factory toEvaluator(Function<Expression, ExpressionEv
         if (format == null) {
             return new DateParseConstantEvaluator.Factory(source(), fieldEvaluator, DEFAULT_DATE_TIME_FORMATTER);
         }
-        if (EsqlDataTypes.isString(format.dataType()) == false) {
+        if (DataType.isString(format.dataType()) == false) {
             throw new IllegalArgumentException("unsupported data type for date_parse [" + format.dataType() + "]");
         }
         if (format.foldable()) {
diff --git a/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/predicate/operator/comparison/InsensitiveEqualsMapper.java b/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/predicate/operator/comparison/InsensitiveEqualsMapper.java
index 0afc9e0280f4c..d11f5c9b68532 100644
--- a/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/predicate/operator/comparison/InsensitiveEqualsMapper.java
+++ b/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/predicate/operator/comparison/InsensitiveEqualsMapper.java
@@ -19,7 +19,6 @@
 import org.elasticsearch.xpack.esql.evaluator.mapper.ExpressionMapper;
 import org.elasticsearch.xpack.esql.expression.function.scalar.math.Cast;
 import org.elasticsearch.xpack.esql.planner.Layout;
-import org.elasticsearch.xpack.esql.type.EsqlDataTypes;
 
 import static org.elasticsearch.xpack.esql.evaluator.EvalMapper.toEvaluator;
 
@@ -36,7 +35,7 @@ public final ExpressionEvaluator.Factory map(InsensitiveEquals bc, Layout layout
         var leftEval = toEvaluator(bc.left(), layout);
         var rightEval = toEvaluator(bc.right(), layout);
         if (leftType == DataType.KEYWORD || leftType == DataType.TEXT) {
-            if (bc.right().foldable() && EsqlDataTypes.isString(rightType)) {
+            if (bc.right().foldable() && DataType.isString(rightType)) {
                 BytesRef rightVal = BytesRefs.toBytesRef(bc.right().fold());
                 Automaton automaton = InsensitiveEquals.automaton(rightVal);
                 return dvrCtx -> new InsensitiveEqualsConstantEvaluator(
diff --git a/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/type/EsqlDataTypes.java b/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/type/EsqlDataTypes.java
index 8a75d3f379dd3..aad9470ecbbb7 100644
--- a/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/type/EsqlDataTypes.java
+++ b/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/type/EsqlDataTypes.java
@@ -8,13 +8,10 @@
 
 import org.elasticsearch.xpack.esql.core.type.DataType;
 
-import java.util.Locale;
-
 import static org.elasticsearch.xpack.esql.core.type.DataType.BYTE;
 import static org.elasticsearch.xpack.esql.core.type.DataType.DATE_PERIOD;
 import static org.elasticsearch.xpack.esql.core.type.DataType.FLOAT;
 import static org.elasticsearch.xpack.esql.core.type.DataType.HALF_FLOAT;
-import static org.elasticsearch.xpack.esql.core.type.DataType.KEYWORD;
 import static org.elasticsearch.xpack.esql.core.type.DataType.NESTED;
 import static org.elasticsearch.xpack.esql.core.type.DataType.NULL;
 import static org.elasticsearch.xpack.esql.core.type.DataType.OBJECT;
@@ -22,7 +19,6 @@
 import static org.elasticsearch.xpack.esql.core.type.DataType.SCALED_FLOAT;
 import static org.elasticsearch.xpack.esql.core.type.DataType.SHORT;
 import static org.elasticsearch.xpack.esql.core.type.DataType.SOURCE;
-import static org.elasticsearch.xpack.esql.core.type.DataType.TEXT;
 import static org.elasticsearch.xpack.esql.core.type.DataType.TIME_DURATION;
 import static org.elasticsearch.xpack.esql.core.type.DataType.UNSUPPORTED;
 import static org.elasticsearch.xpack.esql.core.type.DataType.isNull;
@@ -31,14 +27,6 @@ public final class EsqlDataTypes {
 
     private EsqlDataTypes() {}
 
-    public static DataType fromTypeName(String name) {
-        return DataType.fromTypeName(name.toLowerCase(Locale.ROOT));
-    }
-
-    public static boolean isString(DataType t) {
-        return t == KEYWORD || t == TEXT;
-    }
-
     public static boolean isPrimitive(DataType t) {
         return t != OBJECT && t != NESTED;
     }
@@ -98,7 +86,9 @@ public static boolean areCompatible(DataType left, DataType right) {
         if (left == right) {
             return true;
         } else {
-            return (left == NULL || right == NULL) || (isString(left) && isString(right)) || (left.isNumeric() && right.isNumeric());
+            return (left == NULL || right == NULL)
+                || (DataType.isString(left) && DataType.isString(right))
+                || (left.isNumeric() && right.isNumeric());
         }
     }
 }
diff --git a/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/expression/function/scalar/multivalue/MvConcatTests.java b/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/expression/function/scalar/multivalue/MvConcatTests.java
index 0277093152cba..3c668b6f41d4b 100644
--- a/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/expression/function/scalar/multivalue/MvConcatTests.java
+++ b/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/expression/function/scalar/multivalue/MvConcatTests.java
@@ -16,7 +16,6 @@
 import org.elasticsearch.xpack.esql.core.type.DataType;
 import org.elasticsearch.xpack.esql.expression.function.AbstractScalarFunctionTestCase;
 import org.elasticsearch.xpack.esql.expression.function.TestCaseSupplier;
-import org.elasticsearch.xpack.esql.type.EsqlDataTypes;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -33,11 +32,11 @@ public MvConcatTests(@Name("TestCase") Supplier<TestCaseSupplier.TestCase> testC
     public static Iterable<Object[]> parameters() {
         List<TestCaseSupplier> suppliers = new ArrayList<>();
         for (DataType fieldType : DataType.types()) {
-            if (EsqlDataTypes.isString(fieldType) == false) {
+            if (DataType.isString(fieldType) == false) {
                 continue;
             }
             for (DataType delimType : DataType.types()) {
-                if (EsqlDataTypes.isString(delimType) == false) {
+                if (DataType.isString(delimType) == false) {
                     continue;
                 }
                 for (int l = 1; l < 10; l++) {
diff --git a/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/expression/function/scalar/spatial/BinarySpatialFunctionTestCase.java b/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/expression/function/scalar/spatial/BinarySpatialFunctionTestCase.java
index a30cce9f765ed..4ab1517d0c17a 100644
--- a/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/expression/function/scalar/spatial/BinarySpatialFunctionTestCase.java
+++ b/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/expression/function/scalar/spatial/BinarySpatialFunctionTestCase.java
@@ -27,10 +27,10 @@
 import java.util.stream.Collectors;
 import java.util.stream.IntStream;
 
+import static org.elasticsearch.xpack.esql.core.type.DataType.isString;
 import static org.elasticsearch.xpack.esql.expression.function.scalar.spatial.SpatialRelatesFunction.compatibleTypeNames;
 import static org.elasticsearch.xpack.esql.type.EsqlDataTypes.isSpatial;
 import static org.elasticsearch.xpack.esql.type.EsqlDataTypes.isSpatialGeo;
-import static org.elasticsearch.xpack.esql.type.EsqlDataTypes.isString;
 import static org.hamcrest.Matchers.equalTo;
 
 public abstract class BinarySpatialFunctionTestCase extends AbstractScalarFunctionTestCase {
diff --git a/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/type/MultiTypeEsFieldTests.java b/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/type/MultiTypeEsFieldTests.java
index bebfcd7f7bdbc..0fa8719f17744 100644
--- a/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/type/MultiTypeEsFieldTests.java
+++ b/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/type/MultiTypeEsFieldTests.java
@@ -42,7 +42,7 @@
 import java.util.List;
 import java.util.Map;
 
-import static org.elasticsearch.xpack.esql.type.EsqlDataTypes.isString;
+import static org.elasticsearch.xpack.esql.core.type.DataType.isString;
 
 /**
  * This test was originally based on the tests for sub-classes of EsField, like InvalidMappedFieldTests.