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Live · checked today · 3 UK retailers tracked
Callaway BIG Bertha B21 Driver vs Mizuno ST-G 440 Driver
Quick verdict
Checked daily across 3 UK retailers
Price and availability verdict
Callaway BIG Bertha B21 Driver is currently £179.99 used, while Mizuno ST-G 440 Driver is currently £169.95 used. Against tracked history, Callaway BIG Bertha B21 Driver is 114% above its lowest tracked price and Mizuno ST-G 440 Driver is 19% above its lowest tracked price. Callaway BIG Bertha B21 Driver is currently available from 1 UK retailer, versus 3 for Mizuno ST-G 440 Driver.
Callaway
BIG Bertha B21 Driver
£179.99 used ↑ £149.05 21% below usual Buy £179.99 → at Nearly New Golf ClubsCallaway
BIG Bertha B21 Driver
£179.99 used
↑ £149.05 7 days
21% below usualat Nearly New Golf Clubs
Deal intelligence
Should you buy now, or wait?
Neither is at its low today. The Mizuno ST-G 440 Driver is closest, within 19% of its lowest tracked price. The Callaway BIG Bertha B21 Driver has more room: its tracked low is £139.95.
Callaway · BIG Bertha B21 Driver
Not enough data yet
Today £299 · typical £194.95 · lowest £139.95
On sale 3 times in the last 3 months
Mizuno · ST-G 440 Driver
Not enough data yet
Today £237.95 · typical £279.95 · lowest £199.95
On sale 2 times in the last 3 months
Head to head
Category leaders, from the data on this page
- Cheapest new BIG Bertha B21 £179.99 vs £237.95
- Closest to its tracked low ST-G 440 19% above vs 114%
- Most retailers in stock ST-G 440 3 vs 1
- Cheapest used ST-G 440 from £169.95 vs £179.99
Where to buy
3 UK retailers, checked daily
Price trajectory
How each has moved since we started tracking
Lowest tracked price per day, any condition. Caddence tracks both daily. Shaded spans are days we couldn’t collect prices — the lines break rather than guessing.
Callaway · BIG Bertha B21 Driver
No change
since 9 April 2026
Lowest £139.95 on 2 July 2026
Mizuno · ST-G 440 Driver
↑ £11
since 9 April 2026
Lowest £199.95 on 24 July 2026
New vs used
From used listings we track
Callaway · BIG Bertha B21 Driver
NEW £179.99
USED FROM £179.99
Mizuno · ST-G 440 Driver
NEW £237.95
USED FROM £169.95
Used prices average 92% of new · 3 used listings tracked
Availability by build
Which configurations are in stock right now
| Build | Callaway BIG Bertha B21 Driver | Mizuno ST-G 440 Driver |
|---|---|---|
| Extra Stiff · 9.5° · Used | — | 2 retailers · from £169.95 at Replay Golf → |
| Regular · 10.5° · Left-hand · Used | 1 retailer · from £179.99 at Nearly New Golf Clubs → | — |
| Stiff · 9.5° | — | 1 retailer · from £237.95 at Replay Golf → |
| Stiff · 9.5° · Used | — | 1 retailer · from £239.99 at Mega Golf → |
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Common questions about the Callaway BIG Bertha B21 Driver vs Mizuno ST-G 440 Driver
Prices shown are the cheapest in-stock price per retailer tracked by Caddence, updated daily. Always confirm the final price on the retailer's site.