The spelling of /b/ is always either <b> or <bb>. The /k/ sound is variously <k>, <ck>, <cc>, <c>, or <ch>. I have excluded a few pairs retrieved by the computer which showed the contrast twice, such as baboon/cocoon and bobtail/cocktail, or reversed in complementary positions, sich as back/cab. I have included the inflected forms in pairs such as tubs/tucks and robbed/rocked even though in phonemic transcription they are not minimal. The homograph bow enters several different pairs, and the homograph corps (singular v. plural) pairs with bore and bores.
The contrast is between two plosives, one voiced and one voiceless, very far apart in the mouth. I have never heard of it being a problem, though mishearings might occur with unreleased final sounds.
As usual, I have included inflected forms such as lobs/locks and lobbed/locked even though they are not strictly minimal. See the main page for an explanation.
There are three pairs involving a taboo word: boon/coon, cob/cock and bum/come.
The pair Cox and Box has become proverbial for any interchangeable pair, and is the title of a Sullivan operetta about two men sharing a room and a fiancée and never meeting. Other interesting pairs include
Abe ache aboard accord abscess access abscesses accesses absent accent abuse accuse abused accused abuses accuses abusing accusing B key baa'd card baas cars babe bake babes bakes babel cable babels cables Babs cabs bad cad badge cadge badges cadges badged cadged badger cadger badgers cadgers bail kail bailiff caliph bailiffs caliphs bairn cairn bairns cairns bait Kate baize K's bake cake baked caked bakes cakes baking caking baker caber bakers cabers bald called bale kail balk calk balked calked balking calking balks calks balk cork balked corked balking corking balks corks ball call balled called balling calling balls calls balm calm ban can banned canned banning canning bans cans band canned banded candid bandy candy bandies candies bandying candying banian canyon banians canyons banister canister banisters canisters banker canker bankers cankers banner canna banners cannas bannock Cannock bant cant banted canted banting canting bants cants banter canter bantered cantered bantering cantering banters canters bar car bars cars barb bark barbs barks barbed barked barber barker barbers barkers bard card bards cards bare care bared cared bares cares baring caring barley Cali barn khan barns khans baron Carron barrel carol barrelled carolled barrelling carolling barrels carols barrier carrier barriers carriers Barry Carrie barter carter barters carters base case based cased bases cases basement casement basements casements bash cache bashes caches bashing caching bash cash bashing cashing bashed cashed bashes cashes basin caisson basins caissons bask cask basks casks basket casket baskets caskets bass case basses cases bat cat bats cats batch catch batches catches bate Kate battle cattle batty catty bauble corbel baubles corbels bawd cawed bawds chords bay K bays K's B key B's keys be key being keying bee key bees keys bear care bearing caring bears cares beau Co beep keep beeps keeps beg keg begs kegs Beith Keith belt Celt ben ken bens kens bend kenned Benny Kenny bent Kent berry Kerry bettering Kettering bid kid bidding kidding bids kids bight kite bights kites bind kind binds kinds binder kinder bine kine bird curd birds curds Birtley curtly bit kit bits kits bite kite bites kites bitten kitten blab black blabber blacker blabbing blacking black clack blacked clacked blacking clacking blacks clacks blame claim blamed claimed blames claims blaming claiming blank clank blanks clanks blare Clare blast classed bleat cleat bleats cleats blench clench blenched clenched blenches clenches blenching clenching blew clew blew clue blink clink blinked clinked blinking clinking blinks clinks blinker clinker blinkers clinkers blip clip blips clips blob bloc blobs blocs blob block blobs blocks bloc clock blocs clocks block clock blocks clocks blocked clocked blocking clocking bloke cloak blokes cloaks blot clot blotted clotted blotting clotting blots clots blown clone blows close blue clew blued clewed blues clews bluing clewing blue clue blues clues bluing clying blued clued bluster cluster blustered clustered blustering clustering blusters clusters boar caw boars caws boar core boars cores boar corps boars corps board chord boards chords board cord boarded corded boarding cording boards cords board cored boars cause boast coast boasted coasted boasting coasting boasts coasts boaster coaster boasters coasters boat coat boated coated boating coating boats coats bob cob bobs cobs Bobby cocky bode code boded coded bodes codes bodied codded boffin coffin boffins coffins bog cog bogs cogs boil coil boiled coiled boiling coiling boils coils bold coaled bold cold bolder colder boldest coldest boldly coldly boldness coldness bole coal boles coals bollard collared bolt colt bolts colts bomber comma bombers commas bond conned bone cone boned coned bones cones boning coning bongo Congo bonkers conkers bonkers conquers Bonn con bonny Connie bony coney boo coo booing cooing boos coos book cook booked cooked booking cooking books cooks bookie cookie bookies cookies boon coon boons coons boot coot boots coots booze coos bore caw bores caws bores cause bored chord bore core bored cored bores cores boring coring bore corps bores corps bored cord boss cos bough cow boughs cows bought caught bought court bounty county bounties counties Bourne corn bow Co bow cow bows cows bowed cowed bowing cowing bower cower bowers cowers bowl coal bowling coaling bowled coaled bowls coals bowled cold bowler cola bowlers colas box cocks boxed coxed boxes coxes boxing coxing boy coy bract cracked braes craze brag crag brags crags brain crane brained craned braining craning brains cranes braise craze braised crazed braises crazes brake crake brakes crakes brash crash brave crave braved craved braves craves braving craving brawl crawl brawled crawled brawling crawling brawls crawls brawler crawler brawlers crawlers brazier crazier breast crest breasted crested breasting cresting breasts crests breed creed brew crew brewed crewed brews crews brews cruise briar crier briars criers bride cried brief Crieff Bristol crystal broke croak brook crook brooked crooked brooking crooking brooks crooks Bros cross brown crown browned crowned browning crowning browns crowns bruise cruise bruised cruised bruises cruises bruising cruising bruise crews bruiser cruiser bruisers cruisers brunch crunch brunches crunches brush crush brushed crushed brushes crushes brushing crushing bubble buckle bubbled buckled bubbles buckles bubbling buckling Buckley bubbly bud cud buff cuff buffed cuffed buffing cuffing buffs cuffs built kilt bulb bulk bulbs bulks bum come bumming coming bums comes bur cur burk kirk burks kirks burly curly burlier curlier burliest curliest burr cur burrs curs bursary cursory burst cursed burton curtain burtons curtains Bury Kerry bus cuss buses cusses bushy cushy bustard custard bustards custards but cut buts cuts butt cut butts cuts butting cutting butts cuts butler cutler butlers cutlers butter cutter butters cutters club cluck clubbing clucking clubbed clucked clubs clucks cob cock cobs cocks cobber cocker cobbers cockers cobble cockle cobbles cockles crab crack crabbing cracking crabbed criacked crabs cracks crib crick cribbing cricking cribbed cricked cribs cricks curb kirk curbs kirks daubing Dorking deb Dec dibber dicker dibbers dickers doubling duckling dub duck dubbing ducking dubbed ducked dubs ducks grebe Greek hob hock hobs hocks hobby hockey houseboat housecoat houseboats housecoats jab jack jabbing jacking jabbed jacked jabs jacks Job joke knob knock knobs knocks kobo coco kobos cocos lab lack labs lacks labs lax Lib lick lob lock lobs locks lobbing locking lobbed locked mob mock mobbing mocking mobbed mocked mobs mocks nab knack nabs knacks neighbour nacre nib Nick nibble nickel nibbled nickelled nibbles nickels Oban oaken orb auk pub puck pubs pucks rabbit racket rabbited racketed rabbiting racketing rabbits rackets rib rick ribbing ricking ribbed ricked ribs ricks rob roc rob rock robbed rocked robbing rocking robs rocks robber rocker robbers rockers robbery rockery robberies rockeries rub ruck rubbing rucking rubbed rucked rubs rucks sibyl sickle sibyls sickles slab slack slabs slacks sob sock sobbing socking sobbed socked sobs socks sober soaker sobers soakers stab stack stabbing stacking stabbed stacked stabs stacks stub stuck sub suck subbing sucking subbed sucked subs sucks tab tack tabs tacks tabby tacky tabor taker tabors takers trouble truckle troubled truckled troubles truckles troubling truckling tub tuck tubs tucks Woburn woken
John Higgins, Shaftesbury, January 2010.