diff --git a/cmd/geth/config.go b/cmd/geth/config.go
index ea4e65162997..0050a51b8a26 100644
--- a/cmd/geth/config.go
+++ b/cmd/geth/config.go
@@ -32,6 +32,7 @@ import (
 	"github.com/ethereum/go-ethereum/accounts/scwallet"
 	"github.com/ethereum/go-ethereum/accounts/usbwallet"
 	"github.com/ethereum/go-ethereum/cmd/utils"
+	"github.com/ethereum/go-ethereum/core/rawdb"
 	"github.com/ethereum/go-ethereum/eth/ethconfig"
 	"github.com/ethereum/go-ethereum/internal/ethapi"
 	"github.com/ethereum/go-ethereum/log"
@@ -161,7 +162,24 @@ func makeFullNode(ctx *cli.Context) (*node.Node, ethapi.Backend) {
 	if ctx.GlobalIsSet(utils.OverrideTerminalTotalDifficulty.Name) {
 		cfg.Eth.OverrideTerminalTotalDifficulty = new(big.Int).SetUint64(ctx.GlobalUint64(utils.OverrideTerminalTotalDifficulty.Name))
 	}
-	backend, _ := utils.RegisterEthService(stack, &cfg.Eth)
+	backend, eth := utils.RegisterEthService(stack, &cfg.Eth)
+	// Warn users to migrate if they have a legacy freezer format.
+	if eth != nil {
+		firstIdx := uint64(0)
+		// Hack to speed up check for mainnet because we know
+		// the first non-empty block.
+		ghash := rawdb.ReadCanonicalHash(eth.ChainDb(), 0)
+		if cfg.Eth.NetworkId == 1 && ghash == params.MainnetGenesisHash {
+			firstIdx = 46147
+		}
+		isLegacy, _, err := dbHasLegacyReceipts(eth.ChainDb(), firstIdx)
+		if err != nil {
+			utils.Fatalf("Failed to check db for legacy receipts: %v", err)
+		}
+		if isLegacy {
+			log.Warn("Database has receipts with a legacy format. Please run `geth db freezer-migrate`.")
+		}
+	}
 
 	// Configure GraphQL if requested
 	if ctx.GlobalIsSet(utils.GraphQLEnabledFlag.Name) {
diff --git a/cmd/geth/dbcmd.go b/cmd/geth/dbcmd.go
index 4799a6388a9d..f7bebf56f97a 100644
--- a/cmd/geth/dbcmd.go
+++ b/cmd/geth/dbcmd.go
@@ -35,6 +35,7 @@ import (
 	"github.com/ethereum/go-ethereum/console/prompt"
 	"github.com/ethereum/go-ethereum/core/rawdb"
 	"github.com/ethereum/go-ethereum/core/state/snapshot"
+	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/ethdb"
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/trie"
@@ -72,6 +73,7 @@ Remove blockchain and state databases`,
 			dbImportCmd,
 			dbExportCmd,
 			dbMetadataCmd,
+			dbMigrateFreezerCmd,
 		},
 	}
 	dbInspectCmd = cli.Command{
@@ -251,6 +253,23 @@ WARNING: This is a low-level operation which may cause database corruption!`,
 		},
 		Description: "Shows metadata about the chain status.",
 	}
+	dbMigrateFreezerCmd = cli.Command{
+		Action:    utils.MigrateFlags(freezerMigrate),
+		Name:      "freezer-migrate",
+		Usage:     "Migrate legacy parts of the freezer. (WARNING: may take a long time)",
+		ArgsUsage: "",
+		Flags: []cli.Flag{
+			utils.DataDirFlag,
+			utils.SyncModeFlag,
+			utils.MainnetFlag,
+			utils.RopstenFlag,
+			utils.SepoliaFlag,
+			utils.RinkebyFlag,
+			utils.GoerliFlag,
+		},
+		Description: `The freezer-migrate command checks your database for receipts in a legacy format and updates those.
+WARNING: please back-up the receipt files in your ancients before running this command.`,
+	}
 )
 
 func removeDB(ctx *cli.Context) error {
@@ -750,3 +769,88 @@ func showMetaData(ctx *cli.Context) error {
 	table.Render()
 	return nil
 }
+
+func freezerMigrate(ctx *cli.Context) error {
+	stack, _ := makeConfigNode(ctx)
+	defer stack.Close()
+
+	db := utils.MakeChainDatabase(ctx, stack, false)
+	defer db.Close()
+
+	// Check first block for legacy receipt format
+	numAncients, err := db.Ancients()
+	if err != nil {
+		return err
+	}
+	if numAncients < 1 {
+		log.Info("No receipts in freezer to migrate")
+		return nil
+	}
+
+	isFirstLegacy, firstIdx, err := dbHasLegacyReceipts(db, 0)
+	if err != nil {
+		return err
+	}
+	if !isFirstLegacy {
+		log.Info("No legacy receipts to migrate")
+		return nil
+	}
+
+	log.Info("Starting migration", "ancients", numAncients, "firstLegacy", firstIdx)
+	start := time.Now()
+	if err := db.MigrateTable("receipts", types.ConvertLegacyStoredReceipts); err != nil {
+		return err
+	}
+	if err := db.Close(); err != nil {
+		return err
+	}
+	log.Info("Migration finished", "duration", time.Since(start))
+
+	return nil
+}
+
+// dbHasLegacyReceipts checks freezer entries for legacy receipts. It stops at the first
+// non-empty receipt and checks its format. The index of this first non-empty element is
+// the second return parameter.
+func dbHasLegacyReceipts(db ethdb.Database, firstIdx uint64) (bool, uint64, error) {
+	// Check first block for legacy receipt format
+	numAncients, err := db.Ancients()
+	if err != nil {
+		return false, 0, err
+	}
+	if numAncients < 1 {
+		return false, 0, nil
+	}
+	if firstIdx >= numAncients {
+		return false, firstIdx, nil
+	}
+	var (
+		legacy       bool
+		blob         []byte
+		emptyRLPList = []byte{192}
+	)
+	// Find first block with non-empty receipt, only if
+	// the index is not already provided.
+	if firstIdx == 0 {
+		for i := uint64(0); i < numAncients; i++ {
+			blob, err = db.Ancient("receipts", i)
+			if err != nil {
+				return false, 0, err
+			}
+			if len(blob) == 0 {
+				continue
+			}
+			if !bytes.Equal(blob, emptyRLPList) {
+				firstIdx = i
+				break
+			}
+		}
+	}
+	// Is first non-empty receipt legacy?
+	first, err := db.Ancient("receipts", firstIdx)
+	if err != nil {
+		return false, 0, err
+	}
+	legacy, err = types.IsLegacyStoredReceipts(first)
+	return legacy, firstIdx, err
+}
diff --git a/core/rawdb/database.go b/core/rawdb/database.go
index be66828eeab8..6a38445c4fa6 100644
--- a/core/rawdb/database.go
+++ b/core/rawdb/database.go
@@ -145,6 +145,12 @@ func (db *nofreezedb) ReadAncients(fn func(reader ethdb.AncientReader) error) (e
 	return fn(db)
 }
 
+// MigrateTable processes the entries in a given table in sequence
+// converting them to a new format if they're of an old format.
+func (db *nofreezedb) MigrateTable(kind string, convert convertLegacyFn) error {
+	return errNotSupported
+}
+
 // NewDatabase creates a high level database on top of a given key-value data
 // store without a freezer moving immutable chain segments into cold storage.
 func NewDatabase(db ethdb.KeyValueStore) ethdb.Database {
diff --git a/core/rawdb/freezer.go b/core/rawdb/freezer.go
index c7008e83f4d4..8266933ee655 100644
--- a/core/rawdb/freezer.go
+++ b/core/rawdb/freezer.go
@@ -19,6 +19,7 @@ package rawdb
 import (
 	"errors"
 	"fmt"
+	"io/ioutil"
 	"math"
 	"os"
 	"path/filepath"
@@ -617,3 +618,116 @@ func (f *freezer) freezeRange(nfdb *nofreezedb, number, limit uint64) (hashes []
 
 	return hashes, err
 }
+
+// convertLegacyFn takes a raw freezer entry in an older format and
+// returns it in the new format.
+type convertLegacyFn = func([]byte) ([]byte, error)
+
+// MigrateTable processes the entries in a given table in sequence
+// converting them to a new format if they're of an old format.
+func (f *freezer) MigrateTable(kind string, convert convertLegacyFn) error {
+	if f.readonly {
+		return errReadOnly
+	}
+	f.writeLock.Lock()
+	defer f.writeLock.Unlock()
+
+	table, ok := f.tables[kind]
+	if !ok {
+		return errUnknownTable
+	}
+	// forEach iterates every entry in the table serially and in order, calling `fn`
+	// with the item as argument. If `fn` returns an error the iteration stops
+	// and that error will be returned.
+	forEach := func(t *freezerTable, offset uint64, fn func(uint64, []byte) error) error {
+		var (
+			items     = atomic.LoadUint64(&t.items)
+			batchSize = uint64(1024)
+			maxBytes  = uint64(1024 * 1024)
+		)
+		for i := offset; i < items; {
+			if i+batchSize > items {
+				batchSize = items - i
+			}
+			data, err := t.RetrieveItems(i, batchSize, maxBytes)
+			if err != nil {
+				return err
+			}
+			for j, item := range data {
+				if err := fn(i+uint64(j), item); err != nil {
+					return err
+				}
+			}
+			i += uint64(len(data))
+		}
+		return nil
+	}
+	// TODO(s1na): This is a sanity-check since as of now no process does tail-deletion. But the migration
+	// process assumes no deletion at tail and needs to be modified to account for that.
+	if table.itemOffset > 0 || table.itemHidden > 0 {
+		return fmt.Errorf("migration not supported for tail-deleted freezers")
+	}
+	ancientsPath := filepath.Dir(table.index.Name())
+	// Set up new dir for the migrated table, the content of which
+	// we'll at the end move over to the ancients dir.
+	migrationPath := filepath.Join(ancientsPath, "migration")
+	newTable, err := NewFreezerTable(migrationPath, kind, FreezerNoSnappy[kind], false)
+	if err != nil {
+		return err
+	}
+	var (
+		batch  = newTable.newBatch()
+		out    []byte
+		start  = time.Now()
+		logged = time.Now()
+		offset = newTable.items
+	)
+	if offset > 0 {
+		log.Info("found previous migration attempt", "migrated", offset)
+	}
+	// Iterate through entries and transform them
+	if err := forEach(table, offset, func(i uint64, blob []byte) error {
+		if i%10000 == 0 && time.Since(logged) > 16*time.Second {
+			log.Info("Processing legacy elements", "count", i, "elapsed", common.PrettyDuration(time.Since(start)))
+			logged = time.Now()
+		}
+		out, err = convert(blob)
+		if err != nil {
+			return err
+		}
+		if err := batch.AppendRaw(i, out); err != nil {
+			return err
+		}
+		return nil
+	}); err != nil {
+		return err
+	}
+	if err := batch.commit(); err != nil {
+		return err
+	}
+	log.Info("Replacing old table files with migrated ones", "elapsed", common.PrettyDuration(time.Since(start)))
+	// Release and delete old table files. Note this won't
+	// delete the index file.
+	table.releaseFilesAfter(0, true)
+
+	if err := newTable.Close(); err != nil {
+		return err
+	}
+	files, err := ioutil.ReadDir(migrationPath)
+	if err != nil {
+		return err
+	}
+	// Move migrated files to ancients dir.
+	for _, f := range files {
+		// This will replace the old index file as a side-effect.
+		if err := os.Rename(filepath.Join(migrationPath, f.Name()), filepath.Join(ancientsPath, f.Name())); err != nil {
+			return err
+		}
+	}
+	// Delete by now empty dir.
+	if err := os.Remove(migrationPath); err != nil {
+		return err
+	}
+
+	return nil
+}
diff --git a/core/rawdb/freezer_test.go b/core/rawdb/freezer_test.go
index 74e3d660cb10..b3fd3059e750 100644
--- a/core/rawdb/freezer_test.go
+++ b/core/rawdb/freezer_test.go
@@ -24,6 +24,7 @@ import (
 	"math/big"
 	"math/rand"
 	"os"
+	"path"
 	"sync"
 	"testing"
 
@@ -337,3 +338,92 @@ func checkAncientCount(t *testing.T, f *freezer, kind string, n uint64) {
 		t.Errorf("Ancient(%q, %d) returned unexpected error %q", kind, index, err)
 	}
 }
+
+func TestRenameWindows(t *testing.T) {
+	var (
+		fname   = "file.bin"
+		fname2  = "file2.bin"
+		data    = []byte{1, 2, 3, 4}
+		data2   = []byte{2, 3, 4, 5}
+		data3   = []byte{3, 5, 6, 7}
+		dataLen = 4
+	)
+
+	// Create 2 temp dirs
+	dir1, err := os.MkdirTemp("", "rename-test")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.Remove(dir1)
+	dir2, err := os.MkdirTemp("", "rename-test")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.Remove(dir2)
+
+	// Create file in dir1 and fill with data
+	f, err := os.Create(path.Join(dir1, fname))
+	if err != nil {
+		t.Fatal(err)
+	}
+	f2, err := os.Create(path.Join(dir1, fname2))
+	if err != nil {
+		t.Fatal(err)
+	}
+	f3, err := os.Create(path.Join(dir2, fname2))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if _, err := f.Write(data); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := f2.Write(data2); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := f3.Write(data3); err != nil {
+		t.Fatal(err)
+	}
+	if err := f.Close(); err != nil {
+		t.Fatal(err)
+	}
+	if err := f2.Close(); err != nil {
+		t.Fatal(err)
+	}
+	if err := f3.Close(); err != nil {
+		t.Fatal(err)
+	}
+	if err := os.Rename(f.Name(), path.Join(dir2, fname)); err != nil {
+		t.Fatal(err)
+	}
+	if err := os.Rename(f2.Name(), path.Join(dir2, fname2)); err != nil {
+		t.Fatal(err)
+	}
+
+	// Check file contents
+	f, err = os.Open(path.Join(dir2, fname))
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer f.Close()
+	defer os.Remove(f.Name())
+	buf := make([]byte, dataLen)
+	if _, err := f.Read(buf); err != nil {
+		t.Fatal(err)
+	}
+	if !bytes.Equal(buf, data) {
+		t.Errorf("unexpected file contents. Got %v\n", buf)
+	}
+
+	f, err = os.Open(path.Join(dir2, fname2))
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer f.Close()
+	defer os.Remove(f.Name())
+	if _, err := f.Read(buf); err != nil {
+		t.Fatal(err)
+	}
+	if !bytes.Equal(buf, data2) {
+		t.Errorf("unexpected file contents. Got %v\n", buf)
+	}
+}
diff --git a/core/rawdb/table.go b/core/rawdb/table.go
index bb65e20a43a2..5eadf5f7c159 100644
--- a/core/rawdb/table.go
+++ b/core/rawdb/table.go
@@ -113,6 +113,12 @@ func (t *table) Sync() error {
 	return t.db.Sync()
 }
 
+// MigrateTable processes the entries in a given table in sequence
+// converting them to a new format if they're of an old format.
+func (t *table) MigrateTable(kind string, convert convertLegacyFn) error {
+	return t.db.MigrateTable(kind, convert)
+}
+
 // Put inserts the given value into the database at a prefixed version of the
 // provided key.
 func (t *table) Put(key []byte, value []byte) error {
diff --git a/core/types/legacy.go b/core/types/legacy.go
new file mode 100644
index 000000000000..9254381b1e11
--- /dev/null
+++ b/core/types/legacy.go
@@ -0,0 +1,53 @@
+// Copyright 2021 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package types
+
+import (
+	"errors"
+
+	"github.com/ethereum/go-ethereum/rlp"
+)
+
+// IsLegacyStoredReceipts tries to parse the RLP-encoded blob
+// first as an array of v3 stored receipt, then v4 stored receipt and
+// returns true if successful.
+func IsLegacyStoredReceipts(raw []byte) (bool, error) {
+	var v3 []v3StoredReceiptRLP
+	if err := rlp.DecodeBytes(raw, &v3); err == nil {
+		return true, nil
+	}
+	var v4 []v4StoredReceiptRLP
+	if err := rlp.DecodeBytes(raw, &v4); err == nil {
+		return true, nil
+	}
+	var v5 []storedReceiptRLP
+	// Check to see valid fresh stored receipt
+	if err := rlp.DecodeBytes(raw, &v5); err == nil {
+		return false, nil
+	}
+	return false, errors.New("value is not a valid receipt encoding")
+}
+
+// ConvertLegacyStoredReceipts takes the RLP encoding of an array of legacy
+// stored receipts and returns a fresh RLP-encoded stored receipt.
+func ConvertLegacyStoredReceipts(raw []byte) ([]byte, error) {
+	var receipts []ReceiptForStorage
+	if err := rlp.DecodeBytes(raw, &receipts); err != nil {
+		return nil, err
+	}
+	return rlp.EncodeToBytes(&receipts)
+}
diff --git a/ethdb/database.go b/ethdb/database.go
index d749c255b9fd..b2e7c7228a0a 100644
--- a/ethdb/database.go
+++ b/ethdb/database.go
@@ -124,6 +124,11 @@ type AncientWriter interface {
 
 	// Sync flushes all in-memory ancient store data to disk.
 	Sync() error
+
+	// MigrateTable processes and migrates entries of a given table to a new format.
+	// The second argument is a function that takes a raw entry and returns it
+	// in the newest format.
+	MigrateTable(string, func([]byte) ([]byte, error)) error
 }
 
 // AncientWriteOp is given to the function argument of ModifyAncients.