DEWALT Battery Adapter 18V to 20V - Use 20V MAX Batteries in 18V Tools

Our review of the DEWALT Battery Adapter 18V to 20V looks at a simple, practical solution for users who want to keep older 18V tools relevant. The bottom line: this adapter is for owners of legacy 18V DEWALT drills, sanders and other tools who already have 20V MAX batteries and want to use them without buying new tools. It converts selected 20V MAX battery sizes to fit most 18V tool platforms, and the biggest reason to buy is straightforward compatibility that extends the life of existing tools.

Key Features

• 20V to 18V compatibility: Lets several 20V MAX battery sizes power most 18V DEWALT tools so old tools remain useful.
• Battery size support: Works with 1.5 Ah, 2.0 Ah, 3.0 Ah, 4.0 Ah and 5.0 Ah XR batteries, offering flexibility across common pack capacities.
• Charger requirement: Requires use of a 20V MAX DEWALT charger, so users keep charging within the 20V system for safety and reliability.
• Tool protection note: Not to be used with premium batteries in DC970 or DC759 tools, preventing incompatible pairings that could damage tools.
• FLEXVOLT exclusion: Will not work with 20V/60V FLEXVOLT batteries, avoiding confusion with DEWALT's multi-voltage packs.

Who It's For

This adapter is aimed at DIYers and tradespeople who already own a mix of 18V tools and 20V MAX batteries and want a cost-effective way to unify their battery inventory. It is especially useful if a user has several 20V XR packs in the supported capacities and wants to keep older 18V tools in service without buying replacement 20V tools.

Those who should look elsewhere include anyone relying on FLEXVOLT packs or owners of tools that require premium batteries specified for DC970 or DC759 tools, since the adapter explicitly excludes those batteries and tool combinations. If you need wide compatibility with every DEWALT battery family, this adapter is not the match.

Pros & Cons

Pros

• Keeps older 18V tools useful by allowing selected 20V MAX batteries to be used in place of 18V packs.
• Supports a range of common XR battery capacities so users can use what they already own.
• Clear limitations prevent incompatible pairings with FLEXVOLT and some premium-tool batteries, reducing risk of misuse.

Cons

• Some users report the adapter can be difficult to remove or feels tight, which can be inconvenient during frequent battery swaps.
• Does not work with FLEXVOLT packs and is not for use with certain premium-tool battery pairings, limiting universal use.

Specifications

Product	DEWALT Battery Adapter 18V to 20V (DCA1820)
Primary function	Allows use of select 20V MAX batteries in most 18V DEWALT tools
Compatible battery sizes	1.5 Ah, 2.0 Ah, 3.0 Ah, 4.0 Ah, 5.0 Ah XR
Charger requirement	Requires 20V MAX DEWALT charger (charger not included)
Incompatible batteries	20V/60V FLEXVOLT and premium batteries for DC970 or DC759 tools
Included	Adapter only; charger and batteries sold separately

Our Verdict

The DEWALT 18V to 20V adapter is a practical, cost-saving tool for anyone who wants to use existing 20V MAX XR batteries with older 18V DEWALT tools. It is good value for users with supported battery sizes and who do not rely on FLEXVOLT or the excluded premium-tool batteries, though the fit can be snug and removal may be awkward for some.

Frequently Asked Questions

Will this adapter work with FLEXVOLT batteries?
No, the adapter will not work with 20V/60V FLEXVOLT batteries.

Do I need a special charger to use this adapter?
Yes, you must use a 20V MAX DEWALT charger; the adapter does not include a charger.

Are all 20V DEWALT batteries supported?
No, only the 1.5 Ah, 2.0 Ah, 3.0 Ah, 4.0 Ah and 5.0 Ah XR batteries are compatible, and premium batteries for DC970 or DC759 tools are excluded.