diff --git a/cf/src/connection.js b/cf/src/connection.js
index 8e79170a..1b768cfc 100644
--- a/cf/src/connection.js
+++ b/cf/src/connection.js
@@ -958,6 +958,7 @@ function Connection(options, queues = {}, { onopen = noop, onend = noop, onclose
         return b.i32(0xFFFFFFFF)
 
       type = types[i]
+      x = options.transform.value.to ? options.transform.value.to(x, { type }) : x
       parameters[i] = x = type in options.serializers
         ? options.serializers[type](x)
         : '' + x
diff --git a/cf/src/types.js b/cf/src/types.js
index aa2ead29..712ee1b4 100644
--- a/cf/src/types.js
+++ b/cf/src/types.js
@@ -341,7 +341,9 @@ function createJsonTransform(fn) {
     return typeof x === 'object' && x !== null && (column.type === 114 || column.type === 3802)
       ? Array.isArray(x)
         ? x.map(x => jsonTransform(x, column))
-        : Object.entries(x).reduce((acc, [k, v]) => Object.assign(acc, { [fn(k)]: jsonTransform(v, column) }), {})
+        : Object.getPrototypeOf(x) === Object.prototype || Object.getPrototypeOf(x) === null
+          ? Object.entries(x).reduce((acc, [k, v]) => Object.assign(acc, { [fn(k)]: jsonTransform(v, column) }), {})
+          : x
       : x
   }
 }
@@ -349,20 +351,26 @@ function createJsonTransform(fn) {
 toCamel.column = { from: toCamel }
 toCamel.value = { from: createJsonTransform(toCamel) }
 fromCamel.column = { to: fromCamel }
+fromCamel.value = { to: createJsonTransform(fromCamel) }
 
 export const camel = { ...toCamel }
 camel.column.to = fromCamel
+camel.value.to = fromCamel.value.to
 
 toPascal.column = { from: toPascal }
 toPascal.value = { from: createJsonTransform(toPascal) }
 fromPascal.column = { to: fromPascal }
+fromPascal.value = { to: createJsonTransform(fromPascal) }
 
 export const pascal = { ...toPascal }
 pascal.column.to = fromPascal
+pascal.value.to = fromPascal.value.to
 
 toKebab.column = { from: toKebab }
 toKebab.value = { from: createJsonTransform(toKebab) }
 fromKebab.column = { to: fromKebab }
+fromKebab.value = { to: createJsonTransform(fromKebab) }
 
 export const kebab = { ...toKebab }
 kebab.column.to = fromKebab
+kebab.value.to = fromKebab.value.to
diff --git a/cjs/src/connection.js b/cjs/src/connection.js
index 07f67167..4ce3f9b3 100644
--- a/cjs/src/connection.js
+++ b/cjs/src/connection.js
@@ -956,6 +956,7 @@ function Connection(options, queues = {}, { onopen = noop, onend = noop, onclose
         return b.i32(0xFFFFFFFF)
 
       type = types[i]
+      x = options.transform.value.to ? options.transform.value.to(x, { type }) : x
       parameters[i] = x = type in options.serializers
         ? options.serializers[type](x)
         : '' + x
diff --git a/cjs/src/types.js b/cjs/src/types.js
index 0578284c..44a35068 100644
--- a/cjs/src/types.js
+++ b/cjs/src/types.js
@@ -340,7 +340,9 @@ function createJsonTransform(fn) {
     return typeof x === 'object' && x !== null && (column.type === 114 || column.type === 3802)
       ? Array.isArray(x)
         ? x.map(x => jsonTransform(x, column))
-        : Object.entries(x).reduce((acc, [k, v]) => Object.assign(acc, { [fn(k)]: jsonTransform(v, column) }), {})
+        : Object.getPrototypeOf(x) === Object.prototype || Object.getPrototypeOf(x) === null
+          ? Object.entries(x).reduce((acc, [k, v]) => Object.assign(acc, { [fn(k)]: jsonTransform(v, column) }), {})
+          : x
       : x
   }
 }
@@ -348,20 +350,26 @@ function createJsonTransform(fn) {
 toCamel.column = { from: toCamel }
 toCamel.value = { from: createJsonTransform(toCamel) }
 fromCamel.column = { to: fromCamel }
+fromCamel.value = { to: createJsonTransform(fromCamel) }
 
 const camel = module.exports.camel = { ...toCamel }
 camel.column.to = fromCamel
+camel.value.to = fromCamel.value.to
 
 toPascal.column = { from: toPascal }
 toPascal.value = { from: createJsonTransform(toPascal) }
 fromPascal.column = { to: fromPascal }
+fromPascal.value = { to: createJsonTransform(fromPascal) }
 
 const pascal = module.exports.pascal = { ...toPascal }
 pascal.column.to = fromPascal
+pascal.value.to = fromPascal.value.to
 
 toKebab.column = { from: toKebab }
 toKebab.value = { from: createJsonTransform(toKebab) }
 fromKebab.column = { to: fromKebab }
+fromKebab.value = { to: createJsonTransform(fromKebab) }
 
 const kebab = module.exports.kebab = { ...toKebab }
 kebab.column.to = fromKebab
+kebab.value.to = fromKebab.value.to
diff --git a/cjs/tests/index.js b/cjs/tests/index.js
index 85d1aa46..83970b5d 100644
--- a/cjs/tests/index.js
+++ b/cjs/tests/index.js
@@ -106,6 +106,77 @@ t('Json', async() => {
   return ['hello,42', [x.a, x.b].join()]
 })
 
+t('Json transform parameter keys', async() => {
+  const sql = postgres({
+    ...options,
+    transform: postgres.camel
+  })
+  const x = (await sql`select ${ sql.json({ aTest: 1 }) }->>'a_test' as x`)[0].x
+  return ['1', x]
+})
+
+t('Json without transform keeps parameter keys', async() => {
+  const x = (await sql`select ${ sql.json({ aTest: 1 }) }->>'aTest' as x`)[0].x
+  return ['1', x]
+})
+
+t('Json transform nested parameter keys', async() => {
+  const sql = postgres({
+    ...options,
+    transform: postgres.camel
+  })
+  const x = (await sql`
+    select ${ sql.json({ aTest: [{ bTest: 1 }, { bTest: 2 }] }) }#>>'{a_test,1,b_test}' as x
+  `)[0].x
+  return ['2', x]
+})
+
+t('Json transform typed json parameters', async() => {
+  const sql = postgres({
+    ...options,
+    transform: postgres.camel
+  })
+  const x = (await sql`select ${ sql.typed({ aTest: 1 }, 114) }->>'a_test' as x`)[0].x
+  return ['1', x]
+})
+
+t('Json transform implicit jsonb parameters', async() => {
+  const sql = postgres({
+    ...options,
+    transform: postgres.camel
+  })
+  const x = (await sql`select ${ { aTest: 1 } }::jsonb->>'a_test' as x`)[0].x
+  return ['1', x]
+})
+
+t('Json transform implicit json parameters', async() => {
+  const sql = postgres({
+    ...options,
+    transform: postgres.camel
+  })
+  const x = (await sql`select ${ { aTest: 1 } }::json->>'a_test' as x`)[0].x
+  return ['1', x]
+})
+
+t('Json transform result keys', async() => {
+  const sql = postgres({
+    ...options,
+    transform: postgres.camel
+  })
+  const x = (await sql`select '{"a_test":1}'::jsonb as x`)[0].x
+  return [1, x.aTest]
+})
+
+t('Json transform does not transform parameter values with .toJSON()', async() => {
+  const now = new Date()
+  const sql = postgres({
+    ...options,
+    transform: postgres.camel
+  })
+  const x = (await sql`select ${ sql.json({ aTest: now }) }->>'a_test' as x`)[0].x
+  return [now.toJSON(), x]
+})
+
 t('implicit json', async() => {
   const x = (await sql`select ${ { a: 'hello', b: 42 } }::json as x`)[0].x
   return ['hello,42', [x.a, x.b].join()]
diff --git a/deno/src/connection.js b/deno/src/connection.js
index 796725de..bce667e3 100644
--- a/deno/src/connection.js
+++ b/deno/src/connection.js
@@ -959,6 +959,7 @@ function Connection(options, queues = {}, { onopen = noop, onend = noop, onclose
         return b.i32(0xFFFFFFFF)
 
       type = types[i]
+      x = options.transform.value.to ? options.transform.value.to(x, { type }) : x
       parameters[i] = x = type in options.serializers
         ? options.serializers[type](x)
         : '' + x
diff --git a/deno/src/types.js b/deno/src/types.js
index ea0da6a2..6e57930b 100644
--- a/deno/src/types.js
+++ b/deno/src/types.js
@@ -341,7 +341,9 @@ function createJsonTransform(fn) {
     return typeof x === 'object' && x !== null && (column.type === 114 || column.type === 3802)
       ? Array.isArray(x)
         ? x.map(x => jsonTransform(x, column))
-        : Object.entries(x).reduce((acc, [k, v]) => Object.assign(acc, { [fn(k)]: jsonTransform(v, column) }), {})
+        : Object.getPrototypeOf(x) === Object.prototype || Object.getPrototypeOf(x) === null
+          ? Object.entries(x).reduce((acc, [k, v]) => Object.assign(acc, { [fn(k)]: jsonTransform(v, column) }), {})
+          : x
       : x
   }
 }
@@ -349,20 +351,26 @@ function createJsonTransform(fn) {
 toCamel.column = { from: toCamel }
 toCamel.value = { from: createJsonTransform(toCamel) }
 fromCamel.column = { to: fromCamel }
+fromCamel.value = { to: createJsonTransform(fromCamel) }
 
 export const camel = { ...toCamel }
 camel.column.to = fromCamel
+camel.value.to = fromCamel.value.to
 
 toPascal.column = { from: toPascal }
 toPascal.value = { from: createJsonTransform(toPascal) }
 fromPascal.column = { to: fromPascal }
+fromPascal.value = { to: createJsonTransform(fromPascal) }
 
 export const pascal = { ...toPascal }
 pascal.column.to = fromPascal
+pascal.value.to = fromPascal.value.to
 
 toKebab.column = { from: toKebab }
 toKebab.value = { from: createJsonTransform(toKebab) }
 fromKebab.column = { to: fromKebab }
+fromKebab.value = { to: createJsonTransform(fromKebab) }
 
 export const kebab = { ...toKebab }
 kebab.column.to = fromKebab
+kebab.value.to = fromKebab.value.to
diff --git a/deno/tests/index.js b/deno/tests/index.js
index cc2a2518..4542db42 100644
--- a/deno/tests/index.js
+++ b/deno/tests/index.js
@@ -108,6 +108,77 @@ t('Json', async() => {
   return ['hello,42', [x.a, x.b].join()]
 })
 
+t('Json transform parameter keys', async() => {
+  const sql = postgres({
+    ...options,
+    transform: postgres.camel
+  })
+  const x = (await sql`select ${ sql.json({ aTest: 1 }) }->>'a_test' as x`)[0].x
+  return ['1', x]
+})
+
+t('Json without transform keeps parameter keys', async() => {
+  const x = (await sql`select ${ sql.json({ aTest: 1 }) }->>'aTest' as x`)[0].x
+  return ['1', x]
+})
+
+t('Json transform nested parameter keys', async() => {
+  const sql = postgres({
+    ...options,
+    transform: postgres.camel
+  })
+  const x = (await sql`
+    select ${ sql.json({ aTest: [{ bTest: 1 }, { bTest: 2 }] }) }#>>'{a_test,1,b_test}' as x
+  `)[0].x
+  return ['2', x]
+})
+
+t('Json transform typed json parameters', async() => {
+  const sql = postgres({
+    ...options,
+    transform: postgres.camel
+  })
+  const x = (await sql`select ${ sql.typed({ aTest: 1 }, 114) }->>'a_test' as x`)[0].x
+  return ['1', x]
+})
+
+t('Json transform implicit jsonb parameters', async() => {
+  const sql = postgres({
+    ...options,
+    transform: postgres.camel
+  })
+  const x = (await sql`select ${ { aTest: 1 } }::jsonb->>'a_test' as x`)[0].x
+  return ['1', x]
+})
+
+t('Json transform implicit json parameters', async() => {
+  const sql = postgres({
+    ...options,
+    transform: postgres.camel
+  })
+  const x = (await sql`select ${ { aTest: 1 } }::json->>'a_test' as x`)[0].x
+  return ['1', x]
+})
+
+t('Json transform result keys', async() => {
+  const sql = postgres({
+    ...options,
+    transform: postgres.camel
+  })
+  const x = (await sql`select '{"a_test":1}'::jsonb as x`)[0].x
+  return [1, x.aTest]
+})
+
+t('Json transform does not transform parameter values with .toJSON()', async() => {
+  const now = new Date()
+  const sql = postgres({
+    ...options,
+    transform: postgres.camel
+  })
+  const x = (await sql`select ${ sql.json({ aTest: now }) }->>'a_test' as x`)[0].x
+  return [now.toJSON(), x]
+})
+
 t('implicit json', async() => {
   const x = (await sql`select ${ { a: 'hello', b: 42 } }::json as x`)[0].x
   return ['hello,42', [x.a, x.b].join()]
diff --git a/deno/types/index.d.ts b/deno/types/index.d.ts
index 85112eda..36613696 100644
--- a/deno/types/index.d.ts
+++ b/deno/types/index.d.ts
@@ -236,7 +236,7 @@ declare namespace postgres {
   function toPascal(str: string): string;
   namespace toPascal {
     namespace column { function from(str: string): string; }
-    namespace value { function from(str: unknown, column: Column<string>): string }
+    namespace value { function from(str: unknown, column: Column<string>): unknown }
   }
   /**
    * Convert a PascalCase string to snake_case.
@@ -246,6 +246,7 @@ declare namespace postgres {
   function fromPascal(str: string): string;
   namespace fromPascal {
     namespace column { function to(str: string): string }
+    namespace value { function to(str: unknown, column: Column<string>): unknown }
   }
   /**
    * Convert snake_case to and from PascalCase.
@@ -255,7 +256,10 @@ declare namespace postgres {
       function from(str: string): string;
       function to(str: string): string;
     }
-    namespace value { function from(str: unknown, column: Column<string>): string }
+    namespace value {
+      function from(str: unknown, column: Column<string>): unknown;
+      function to(str: unknown, column: Column<string>): unknown;
+    }
   }
   /**
    * Convert a snake_case string to camelCase.
@@ -265,7 +269,7 @@ declare namespace postgres {
   function toCamel(str: string): string;
   namespace toCamel {
     namespace column { function from(str: string): string; }
-    namespace value { function from(str: unknown, column: Column<string>): string }
+    namespace value { function from(str: unknown, column: Column<string>): unknown }
   }
   /**
    * Convert a camelCase string to snake_case.
@@ -275,6 +279,7 @@ declare namespace postgres {
   function fromCamel(str: string): string;
   namespace fromCamel {
     namespace column { function to(str: string): string }
+    namespace value { function to(str: unknown, column: Column<string>): unknown }
   }
   /**
    * Convert snake_case to and from camelCase.
@@ -284,7 +289,10 @@ declare namespace postgres {
       function from(str: string): string;
       function to(str: string): string;
     }
-    namespace value { function from(str: unknown, column: Column<string>): string }
+    namespace value {
+      function from(str: unknown, column: Column<string>): unknown;
+      function to(str: unknown, column: Column<string>): unknown;
+    }
   }
   /**
    * Convert a snake_case string to kebab-case.
@@ -294,7 +302,7 @@ declare namespace postgres {
   function toKebab(str: string): string;
   namespace toKebab {
     namespace column { function from(str: string): string; }
-    namespace value { function from(str: unknown, column: Column<string>): string }
+    namespace value { function from(str: unknown, column: Column<string>): unknown }
   }
   /**
    * Convert a kebab-case string to snake_case.
@@ -304,6 +312,7 @@ declare namespace postgres {
   function fromKebab(str: string): string;
   namespace fromKebab {
     namespace column { function to(str: string): string }
+    namespace value { function to(str: unknown, column: Column<string>): unknown }
   }
   /**
    * Convert snake_case to and from kebab-case.
@@ -313,7 +322,10 @@ declare namespace postgres {
       function from(str: string): string;
       function to(str: string): string;
     }
-    namespace value { function from(str: unknown, column: Column<string>): string }
+    namespace value {
+      function from(str: unknown, column: Column<string>): unknown;
+      function to(str: unknown, column: Column<string>): unknown;
+    }
   }
 
   const BigInt: PostgresType<bigint>;
@@ -404,7 +416,7 @@ declare namespace postgres {
       /** Transform function for values in result rows */
       from: ((value: any, column?: Column<string>) => any) | undefined;
       /** Transform function for interpolated values passed to tagged template literal */
-      to: undefined; // (value: any) => any
+      to: ((value: any, column?: Column<string>) => any) | undefined;
     };
     row: {
       /** Transform function for entire result rows */
diff --git a/src/connection.js b/src/connection.js
index 1b1cccde..0513ce4e 100644
--- a/src/connection.js
+++ b/src/connection.js
@@ -956,6 +956,7 @@ function Connection(options, queues = {}, { onopen = noop, onend = noop, onclose
         return b.i32(0xFFFFFFFF)
 
       type = types[i]
+      x = options.transform.value.to ? options.transform.value.to(x, { type }) : x
       parameters[i] = x = type in options.serializers
         ? options.serializers[type](x)
         : '' + x
diff --git a/src/types.js b/src/types.js
index 7c7c2b93..58ce74cb 100644
--- a/src/types.js
+++ b/src/types.js
@@ -340,7 +340,9 @@ function createJsonTransform(fn) {
     return typeof x === 'object' && x !== null && (column.type === 114 || column.type === 3802)
       ? Array.isArray(x)
         ? x.map(x => jsonTransform(x, column))
-        : Object.entries(x).reduce((acc, [k, v]) => Object.assign(acc, { [fn(k)]: jsonTransform(v, column) }), {})
+        : Object.getPrototypeOf(x) === Object.prototype || Object.getPrototypeOf(x) === null
+          ? Object.entries(x).reduce((acc, [k, v]) => Object.assign(acc, { [fn(k)]: jsonTransform(v, column) }), {})
+          : x
       : x
   }
 }
@@ -348,20 +350,26 @@ function createJsonTransform(fn) {
 toCamel.column = { from: toCamel }
 toCamel.value = { from: createJsonTransform(toCamel) }
 fromCamel.column = { to: fromCamel }
+fromCamel.value = { to: createJsonTransform(fromCamel) }
 
 export const camel = { ...toCamel }
 camel.column.to = fromCamel
+camel.value.to = fromCamel.value.to
 
 toPascal.column = { from: toPascal }
 toPascal.value = { from: createJsonTransform(toPascal) }
 fromPascal.column = { to: fromPascal }
+fromPascal.value = { to: createJsonTransform(fromPascal) }
 
 export const pascal = { ...toPascal }
 pascal.column.to = fromPascal
+pascal.value.to = fromPascal.value.to
 
 toKebab.column = { from: toKebab }
 toKebab.value = { from: createJsonTransform(toKebab) }
 fromKebab.column = { to: fromKebab }
+fromKebab.value = { to: createJsonTransform(fromKebab) }
 
 export const kebab = { ...toKebab }
 kebab.column.to = fromKebab
+kebab.value.to = fromKebab.value.to
diff --git a/tests/index.js b/tests/index.js
index 23e6c4d4..55b54ad7 100644
--- a/tests/index.js
+++ b/tests/index.js
@@ -106,6 +106,77 @@ t('Json', async() => {
   return ['hello,42', [x.a, x.b].join()]
 })
 
+t('Json transform parameter keys', async() => {
+  const sql = postgres({
+    ...options,
+    transform: postgres.camel
+  })
+  const x = (await sql`select ${ sql.json({ aTest: 1 }) }->>'a_test' as x`)[0].x
+  return ['1', x]
+})
+
+t('Json without transform keeps parameter keys', async() => {
+  const x = (await sql`select ${ sql.json({ aTest: 1 }) }->>'aTest' as x`)[0].x
+  return ['1', x]
+})
+
+t('Json transform nested parameter keys', async() => {
+  const sql = postgres({
+    ...options,
+    transform: postgres.camel
+  })
+  const x = (await sql`
+    select ${ sql.json({ aTest: [{ bTest: 1 }, { bTest: 2 }] }) }#>>'{a_test,1,b_test}' as x
+  `)[0].x
+  return ['2', x]
+})
+
+t('Json transform typed json parameters', async() => {
+  const sql = postgres({
+    ...options,
+    transform: postgres.camel
+  })
+  const x = (await sql`select ${ sql.typed({ aTest: 1 }, 114) }->>'a_test' as x`)[0].x
+  return ['1', x]
+})
+
+t('Json transform implicit jsonb parameters', async() => {
+  const sql = postgres({
+    ...options,
+    transform: postgres.camel
+  })
+  const x = (await sql`select ${ { aTest: 1 } }::jsonb->>'a_test' as x`)[0].x
+  return ['1', x]
+})
+
+t('Json transform implicit json parameters', async() => {
+  const sql = postgres({
+    ...options,
+    transform: postgres.camel
+  })
+  const x = (await sql`select ${ { aTest: 1 } }::json->>'a_test' as x`)[0].x
+  return ['1', x]
+})
+
+t('Json transform result keys', async() => {
+  const sql = postgres({
+    ...options,
+    transform: postgres.camel
+  })
+  const x = (await sql`select '{"a_test":1}'::jsonb as x`)[0].x
+  return [1, x.aTest]
+})
+
+t('Json transform does not transform parameter values with .toJSON()', async() => {
+  const now = new Date()
+  const sql = postgres({
+    ...options,
+    transform: postgres.camel
+  })
+  const x = (await sql`select ${ sql.json({ aTest: now }) }->>'a_test' as x`)[0].x
+  return [now.toJSON(), x]
+})
+
 t('implicit json', async() => {
   const x = (await sql`select ${ { a: 'hello', b: 42 } }::json as x`)[0].x
   return ['hello,42', [x.a, x.b].join()]
diff --git a/types/index.d.ts b/types/index.d.ts
index 13c3432f..c165c452 100644
--- a/types/index.d.ts
+++ b/types/index.d.ts
@@ -234,7 +234,7 @@ declare namespace postgres {
   function toPascal(str: string): string;
   namespace toPascal {
     namespace column { function from(str: string): string; }
-    namespace value { function from(str: unknown, column: Column<string>): string }
+    namespace value { function from(str: unknown, column: Column<string>): unknown }
   }
   /**
    * Convert a PascalCase string to snake_case.
@@ -244,6 +244,7 @@ declare namespace postgres {
   function fromPascal(str: string): string;
   namespace fromPascal {
     namespace column { function to(str: string): string }
+    namespace value { function to(str: unknown, column: Column<string>): unknown }
   }
   /**
    * Convert snake_case to and from PascalCase.
@@ -253,7 +254,10 @@ declare namespace postgres {
       function from(str: string): string;
       function to(str: string): string;
     }
-    namespace value { function from(str: unknown, column: Column<string>): string }
+    namespace value {
+      function from(str: unknown, column: Column<string>): unknown;
+      function to(str: unknown, column: Column<string>): unknown;
+    }
   }
   /**
    * Convert a snake_case string to camelCase.
@@ -263,7 +267,7 @@ declare namespace postgres {
   function toCamel(str: string): string;
   namespace toCamel {
     namespace column { function from(str: string): string; }
-    namespace value { function from(str: unknown, column: Column<string>): string }
+    namespace value { function from(str: unknown, column: Column<string>): unknown }
   }
   /**
    * Convert a camelCase string to snake_case.
@@ -273,6 +277,7 @@ declare namespace postgres {
   function fromCamel(str: string): string;
   namespace fromCamel {
     namespace column { function to(str: string): string }
+    namespace value { function to(str: unknown, column: Column<string>): unknown }
   }
   /**
    * Convert snake_case to and from camelCase.
@@ -282,7 +287,10 @@ declare namespace postgres {
       function from(str: string): string;
       function to(str: string): string;
     }
-    namespace value { function from(str: unknown, column: Column<string>): string }
+    namespace value {
+      function from(str: unknown, column: Column<string>): unknown;
+      function to(str: unknown, column: Column<string>): unknown;
+    }
   }
   /**
    * Convert a snake_case string to kebab-case.
@@ -292,7 +300,7 @@ declare namespace postgres {
   function toKebab(str: string): string;
   namespace toKebab {
     namespace column { function from(str: string): string; }
-    namespace value { function from(str: unknown, column: Column<string>): string }
+    namespace value { function from(str: unknown, column: Column<string>): unknown }
   }
   /**
    * Convert a kebab-case string to snake_case.
@@ -302,6 +310,7 @@ declare namespace postgres {
   function fromKebab(str: string): string;
   namespace fromKebab {
     namespace column { function to(str: string): string }
+    namespace value { function to(str: unknown, column: Column<string>): unknown }
   }
   /**
    * Convert snake_case to and from kebab-case.
@@ -311,7 +320,10 @@ declare namespace postgres {
       function from(str: string): string;
       function to(str: string): string;
     }
-    namespace value { function from(str: unknown, column: Column<string>): string }
+    namespace value {
+      function from(str: unknown, column: Column<string>): unknown;
+      function to(str: unknown, column: Column<string>): unknown;
+    }
   }
 
   const BigInt: PostgresType<bigint>;
@@ -402,7 +414,7 @@ declare namespace postgres {
       /** Transform function for values in result rows */
       from: ((value: any, column?: Column<string>) => any) | undefined;
       /** Transform function for interpolated values passed to tagged template literal */
-      to: undefined; // (value: any) => any
+      to: ((value: any, column?: Column<string>) => any) | undefined;
     };
     row: {
       /** Transform function for entire result rows */