The Best Fish Finders

By Alex Clayton · Updated 23 October 2026

A lot of fish finder advice online is written for American lakes, priced in dollars and silent on whether your fishery even allows one. For most UK bank anglers the Garmin STRIKER Cast GPS is the best fish finder to cast from the bank, the Deeper START is the cheapest sensible way in, and kayak or small-boat anglers are better off with a portable or mounted unit that has its own screen.

Check your water’s fishing rules before you buy anything. Some UK coarse fisheries ban fish finders outright, including New Farm Fisheries and Anglers Paradise.

This list is part of our best fishing tackle reviews. Castable (bank) units come first, then portable and mounted units for kayaks and boats. Prices were checked against the makers’ UK stores on 23 October 2026. They change, so check again before you order.

We may earn a commission if you buy through links on this page. It does not change which units make the list or their order.

Unit	Type	Best for	UK price (Oct 2026)
Garmin STRIKER Cast GPS	Castable	Bank anglers who want depth maps	£179.99
Deeper START	Castable	First-time buyers, small lakes	£119.99
Deeper PRO+ 2	Castable	Long casts on big pits	£199.99
Garmin STRIKER Cast (no GPS)	Castable	Regular swims, no mapping needed	£139.99
Deeper CHIRP+ 3 / CHIRP+ 4	Castable	Anglers who have outgrown a PRO+ 2	£289.99 / £379.99
Garmin STRIKER 4 Portable Bundle	Portable	Kayaks and canoes	from £129.99
Garmin STRIKER Vivid range	Mounted	Small boat owners	£219.99 to £569.99
Lowrance Hook Reveal 5	Mounted	A second option to Garmin	Check UK retailers

1. Garmin STRIKER Cast GPS: Best Castable Fish Finder for Bank Anglers

A few fan casts and a slow retrieve will show you depth, bottom shape and weed across a swim before you have set up a rod. The STRIKER Cast GPS costs £179.99 on Garmin’s UK store and was in stock at the time of writing (October 2026), listed as model 010-02246-02.

Garmin’s owner’s manual gives it dual 260/455 kHz sonar reading from under 0.6 m to 45 m. Battery life is about 10 hours of typical use, with roughly an hour and a half to recharge, so a night on the charger covers a long day session.

The built-in GPS receiver is what the extra £40 over item 4 buys. As you retrieve, the unit logs depth against position and builds a contour map of the swim, and Garmin’s UK spec table lists storage for 5,000 waypoints. Mark a gravel bar once and you can find it again next trip.

The limit that catches people out is not casting distance. Sonar data reaches your phone over a 2.4 GHz wireless link with a range of about 60 m (200 ft), and Garmin notes that water conditions affect it. Cast past that and you lose the signal, however far you can throw.

You need a charged phone running Garmin’s app, a strong main line and a secure clip. At 75 g the unit is a real casting weight, so leave the float rod at home.

On a big lake, depth is most of the battle. On Windermere I’ve found that perch and pike hold along drop-offs and weed edges far more than in open water, and knowing where the bottom shelves away is half the job of picking a swim.

Key specs (Garmin):

Sonar: 260/455 kHz
Depth: under 0.6 m to 45 m
Wireless range: about 60 m
Battery: about 10 hours, 1.5 hours to charge
Weight: 75 g, floats, IPX7 rated
5 m tether included

Best for: lake and big-pit bank anglers who want maps. Skip if: your fishery bans fish finders.

2. Deeper START: Cheapest Way to See Depth and Weed From the Bank

Plumbing a swim with a marker float is slow. You cast, count it down, move a few metres and repeat, and you still end up with gaps where the weed starts or the bottom drops away. A cheap castable fish finder answers those questions in a handful of casts.

The Deeper START costs £119.99 on Deeper’s UK store and was not marked as sold out at the time of writing (October 2026). It is the least expensive unit on this list, and the one to buy if you only want to know how deep the swim is and where the weed begins.

Deeper quotes a casting range of up to 50 m, a single 120 kHz beam with a 40 degree cone, a maximum depth of 50 m and up to 6 hours of battery. Those figures come from Deeper’s own pages, so check its spec page before you order in case they change.

The trade-offs are clear. One wide beam shows less detail than the multi-beam CHIRP units further down this list, so telling a fish from a weed bed is harder. There is no GPS mapping either, so you cannot save a contour map of the swim.

Six hours will not cover a dawn-to-dusk session. Charge the START before you leave and carry a power bank for your phone, because the START has no screen of its own and your phone does all the display work.

It suits beginners and pleasure anglers on commercial or club lakes where sonar is allowed. If the swims you fish sit inside 50 m, the casting range will not hold you back.

Quick comparison: the Garmin STRIKER Cast without GPS (item 4) costs £139.99. Garmin quotes about 10 hours of battery against Deeper’s 6, so pay the extra £20 if you fish long sessions.

3. Deeper PRO+ 2: Best for Long Casts and Detailed Lake Maps

Deeper quotes a cast of up to 100 m for the PRO+ 2, double the START’s 50 m. On a big gravel pit that is the difference between mapping the near margin and mapping the bar you actually want to fish.

The PRO+ 2 is listed at £199.99 on Deeper’s UK store at the time of writing (October 2026). Its product page has also shown it as sold out, so confirm it is in stock before you order.

These figures are Deeper’s own, so check its tech specs page before you buy:

Cast range: up to 100 m
Scanning depth: 15 cm to 100 m
Sonar: three CHIRP beams at 47, 20 and 7 degrees
Mapping: built-in GNSS for bathymetric (depth contour) maps
Battery: up to 9 hours
Weight: 90 g

CHIRP sweeps through a range of frequencies rather than sending a single tone, and the narrower beams look at a tighter patch of bottom. That should separate fish, weed and lakebed more clearly than a single wide beam. It will not find fish that are not there.

At 90 g it needs a rod rated for that casting weight. A marker, spod or carp rod will handle it; a float rod or light lure rod will not. Check your rod’s quoted casting weight before the first cast.

Deeper’s UK store also sells the Flexible Arm Mount 2.0 for boat or kayak at £64.99, and the Range Extender Kit for a bait boat at £179.99. Some venues ban bait boats as well as fish finders (New Farm Fisheries and Anglers Paradise both do), so read the rules before you buy either.

Verdict: if you fish big pits and want to map bars at range, start here. If your swims are under 50 m, the START does the job for £80 less.

4. Garmin STRIKER Cast (No GPS): Do You Actually Need Mapping?

If you fish the same few swims on a small club lake, do you need a contour map at all? Usually not, and that is where this version earns its place.

The STRIKER Cast without GPS costs £139.99 on Garmin’s UK store at the time of writing (October 2026), listed as model 010-02246-00 on the same product page as the GPS model. That is £40 less than item 1.

Garmin’s manual gives it the same 260/455 kHz sonar, 0.6 m to 45 m depth range, 10 hour battery and 60 m wireless range as item 1. What it lacks is the built-in GPS receiver, so it cannot save contour maps or waypoints.

You still get depth, bottom shape and weed on your phone in real time. On a water you already know, that live picture is most of the value, and a saved map adds little.

Verdict: buy this if you know your waters and want a live read of depth and features. Pay the extra £40 for the GPS model if you fish big or unfamiliar lakes and want to find marks again.

5. Deeper CHIRP+ 3 and CHIRP+ 4: Premium Castables to Check Before You Pay

Will the most expensive castable put more fish on the bank? Usually not. The fish still have to be in the swim and feeding.

Deeper’s top castables sit well above the PRO+ 2 on price. At the time of writing (October 2026), Deeper’s UK store lists the CHIRP+ 3 at £289.99 and the CHIRP+ 4 at £379.99, which is £90 and £180 more than the PRO+ 2 in item 3.

We have not verified the specs of either unit, so we are not quoting any. Before you pay the premium, open Deeper’s comparison page, put both side by side with the PRO+ 2 and write down the one extra feature you are buying. If you cannot name it, you do not need it.

The older CHIRP+ 2 does not appear on Deeper’s UK store list, so it is not recommended here.

If most of your fishing is from a boat, a mounted unit with its own screen (items 7 and 8) may be better value than either.

Skip if: you have not outgrown a PRO+ 2 and cannot say exactly what the upgrade gives you.

6. Garmin STRIKER 4 Portable Bundle: Best Kayak and Canoe Fish Finder

Holding a phone over the water in the rain while you drift is a good way to lose it. On a kayak you already have a paddle, a rod and a net to manage.

The STRIKER 4 Portable Bundle solves that with its own screen. Garmin’s UK store lists it at £129.99 for model 010-01550-01, in stock at the time of writing (October 2026). A second variant shows £239.99, and we have not confirmed what the difference is, so check which bundle you are buying before you pay.

Garmin’s UK page lists:

A 3.5 in colour display (480 x 320)
Built-in GPS
A carrying case
A 20 ft transducer cable
A weight of 230 g and an IPX7 rating

Garmin describes it as suited to kayak or canoe use, and at £129.99 it is the cheapest kayak fish finder on this list with its own screen and GPS. The screen is small, though, and the page we checked gives no power or battery details. Check what is in the box before your first trip so you are not caught short on the water.

If you already own a Deeper castable, there is another route. Deeper’s Flexible Arm Mount 2.0 (£64.99) holds the sonar on a boat or kayak, though you are back to reading your phone.

A screen in front of you matters most when you are moving. When I troll or drift for pike along the drop-offs on Windermere, knowing the depth as you go is what keeps the lure or bait in the right band.

Still choosing a boat? See our guide to the best fishing kayaks.

Best for: kayak and canoe anglers who want a dedicated screen and GPS for little money. Skip if: you need a large, detailed display.

7. Garmin STRIKER Vivid: Best Mounted Fish Finder for Small Boats

A mounted screen keeps depth and fish in front of you all day, with nothing to cast or retrieve and no phone to keep charged. If you own a dinghy or small boat, this is the step up from a portable unit.

At the time of writing (October 2026), Garmin’s UK store lists the STRIKER Vivid range from £219.99 to £569.99. We have not matched each price to a model. The price varies with the variant (screen size and the transducer supplied), so check the exact model on Garmin’s page.

The headline feature is colour sonar. Colour shading makes it quicker to read a hard bottom against soft silt, and a fish return against weed, than a plain display.

A mounted fish finder needs more setup than anything above:

A mount for the screen
A transducer fitted to the hull or transom
A 12 V battery supply

That makes it a boat owner’s purchase. Hire boats and club boats may not let you fit equipment, so ask before you buy if the boat is not yours.

It suits inshore sea anglers in small boats too, where reading depth over reefs and sandbanks tells you where to drop. Pair it with the right gear from our guide to sea fishing rods.

Verdict: if you own a small boat and fish it regularly, a STRIKER Vivid is the most practical upgrade on this list. Pick the screen size you can read comfortably from your seat.

8. Lowrance Hook Reveal 5: The Mounted Alternative to Garmin

What does DownScan show that standard sonar does not? A picture-like view of what sits directly below the boat, which makes weed beds, snags and structure far easier to read than the usual arches and shading.

That is the main reason to look at the Hook Reveal 5 before committing to Garmin. Lowrance lists these specs on its UK product page, so confirm them there before you order:

A 5 in 800 x 480 SolarMAX display
CHIRP sonar plus DownScan imaging
1 Hz GPS
12 V DC power
IPX7 rating
A weight of about 0.9 lb (0.4 kg)

The 5 in screen is bigger than the 3.5 in display on the STRIKER 4 Portable (item 6), but this is a fixed unit, not a carry-anywhere kit.

Lowrance’s UK page shows no price, so we are not quoting one. Compare prices at UK tackle shops and marine retailers on the day you buy.

Quick comparison: the Hook Reveal 5 and the STRIKER Vivid (item 7) both need a mount, a transducer and 12 V power. Choose on screen size, whether you want DownScan imaging, and the price on the day.

Frequently asked questions

Are fish finders allowed on UK fisheries?

There is no national ban that we could find. Venues and clubs set their own rules, and some ban fish finders. New Farm Fisheries' rule 26 says "No Fish finders or cameras to be used on our lakes", and Anglers Paradise bans them alongside bait boats and drones. Read the venue's fishing rules and ask the bailiff or club secretary before you cast one.

Castable or mounted fish finder: which should I buy?

Buy a castable fish finder if you fish from the bank, a mounted unit if you own a boat, and a portable bundle or a castable on a mount if you fish from a kayak or canoe. Items 1 to 5 cover castables, item 6 covers the STRIKER 4 portable, and items 7 and 8 cover mounted units. If you fish more than one way, buy for the one you do most.

How do you read a fish finder screen?

Start with the depth readout, then the bottom line. A thick, bright bottom usually means hard ground and a thin one soft silt. Weed shows as soft returns above the bottom, fish as arches or icons, and a drop-off as a step in the bottom line. Icons are not always fish. In my experience perch sit tight to structure, so look there first.

How long does a castable fish finder battery last?

Between 6 and 10 hours for the units on this list. Garmin's manual quotes about 10 hours for the STRIKER Cast, and Deeper quotes up to 6 hours for the START and up to 9 for the PRO+ 2. Your phone battery matters just as much, because each castable here uses your phone as the screen, so carry a power bank.

What is the cheapest decent fish finder in the UK?

The Deeper START at £119.99 is the cheapest castable on this list and the cheapest Deeper fish finder we recommend. For kayaks, the Garmin STRIKER 4 Portable Bundle starts from £129.99 and has its own screen. Both prices were checked at the time of writing (October 2026) and change often, so check the maker's UK store before you buy.