List of BBS software
This is a list of notable bulletin board system (BBS) software packages.

Multi-platform 
 Citadel – originally written for the CP/M operating system, had many forks for different systems under different names.
 CONFER – CONFER II on the MTS, CONFER U on Unix and CONFER V on VAX/VMS, written by Robert Parnes starting in 1975.
 Mystic BBS – written by James Coyle with versions for Windows/Linux/ARM Linux/OSX. Past versions: MS-DOS and OS/2.
 Synchronet – Windows/Linux/BSD, past versions: MS-DOS and OS/2.
 WWIV – WWIV v5.x is supported on both Windows 7+ 32bit as well as Linux 32bit and 64bit. Written by Wayne Bell, included WWIVNet. Past versions: MS-DOS and OS/2.
 ENiGMA½ (ENiGMA) – Node.js based. Any computer that can run Node.js can run ENiGMA½. Written by Bryan Ashby.
 PETSCII BBS Builder – Creator: Francesco Sblendorio – Java framework, developer-oriented.

Altos 68000 
 PicoSpan

Amiga based 
AmigaBBS
 Ami-Express – aka "/X", very popular in the crackers/warez software scene.
 C-Net – aka "Cnet"  Still in development today as well. 
DayDream
DLG
Excelsior
Paragon
Spectra – This BBS software, incorporated ALL the Ami-Express BBS functions and more besides. And was released to SysOpS in the crackers/warez software scene.
Tempest
TransAmiga
Zeus
Xenolink
Max's BBS
Max's Pro
 NiKom.

Apple II series 
 CommuniTree – Written by John S. James and online in Santa Cruz, CA in 1978 
 Diversi-Dial (DDial) – Chat-room atmosphere supporting up to 7 incoming lines allowing links to other DDial boards.
 GBBS – Applesoft and assembler-based BBS program by Greg Schaeffer.
 GBBS Pro – based on the ACOS or MACOS (modified ACOS) language.
 HBBS – a hi-resolution graphical dial-up BBS and client package for the Apple II, supported threaded, rich media messages including graphics, shapes, sound, fonts, sprites and animation via its desktop client entitled Pixterm.
 Networks II – by Nick Naimo.
 SBBS – Sonic BBS by Patrick Sonnek.
 TProBBS – message boards and built-in RPG, coded in Applesoft BASIC by Guy T. Rice
 Warp Six – Message forums, file transfer area, door games. Programmed in Applesoft with some assembly for drivers. By Jim Ferr

Apple Macintosh 
 Citadel – including Macadel, MacCitadel.
 FirstClass (SoftArc)
 Hermes
 Red Ryder Host – early example of donationware.
 TeleFinder

Atari 8-bit computer 
 Atari Message Information System – and derivatives
 Carina and Carina II, by Jerry Horanoff and later maintained and expanded by David Hunt: Written in Atari Basic the Carina uses a machine-language 'fossil-driver' called "MOE", for Modem Operating Environment. Moe provided protected memory for user information as Atari Basic does not have global variables.  When modules were loaded and unloaded, they could retrieve needed session data from MOE. Moe redirects all console input and output to and from the RS232 device, simplifying the Basic code considerably, adds speed, and makes the board modifiable from anywhere you can dial in from.  Carina had a working network sharing email between the boards.  One bbs would dial the next on a schedule and exchange messages, forwarding the ones not meant for it specifically.

 BBS Express and BBS Express Professional, by Keith Ledbetter, now Orion Micro Systems. Probably the most used of all Atari Bulletin Board systems. written in machine language they were nevertheless modular and expandible.

 FOREM, FOREM XL, Written in Atari Basic, very popular bbs in the early to mid 1980's.  FOREM stands for Friends Of Ricky E. MOOSE.

 Technical Difficulties BBS, by Kenny Sallot, (The Timelord).  Written in Atari Basic, or Basic XE for the TDXE.  Used primarily on The TARDIS bbs, but several were sold and run by other sysops.

 BBS Construction Set, a BBS written in Atari Basic, highly customizable. Crashes often if tried to be used now. It was an Magazine contributed Atari Basic language bbs. 

 Puff BBS, written in Atari Basic and machine language by Robert Puff of Computer Software Services, Rochester, NY.  Primarily used by his company's BBS, this software supported multiple users on multiple lines and modems via the CSS Multiplexer!  Much admired. No working multiplexer bbs is currently in operation.

Atari ST 

 FaST BBS - Jeff Molofee AKA NeHe
 FoReM BBS ST - Matthew R. Singer(original) Commnet Systems
 ForeSight BBS - Brian Hauer, TSO Software

Commodore computers 
 Apollo64 – by Jeff Heaton.
 Blue Board – by Martin Sikes.
 Superboard – by Greg Francis and Randy Schnedler.
 C*Base – by Gunther Birznieks, Jerome P. Yoner, and David Weinehall.
 C-Net DS2 – by Jim Selleck.
 Cobrasoft BBS – by Ray Bacon.
 Color64 – by Greg Pfountz.   
 Does the Job BBS – by Andrew Bernhardt.
 Ivory BBS – by Bill Jackson. 
 McBBS – by Derek E. McDonald.
 Prometheus – by Martin Brückner.

CP/M 
Many of these needed BYE and KMD to handle modem interactions and file transfers.
 CBBS – The first ever BBS software, written by Ward Christensen.
 Citadel
 MikroKom
 H-Kom
 RBBS – written in Microsoft Basic, really slow login with more than a few users.
 TBBS

Microsoft Windows 
 Power BBS for Windows- c1994 Russell Frey, Hicksville, NY
 Excalibur BBS
 Maximus
Mystic BBS
Synchronet

MS-DOS and compatible 
 Celerity BBS
 Citadel – including DragCit, Cit86, TurboCit, Citadel+
 Ezycom – written by Peter Davies.
 FBB (F6FBB) – packet radio BBS system, still in use.
 GAP BBS By GAP Development. Used CLACom and Clarion as its underlying functionality.  Written and maintained by Kenny Gardner.
 GBBS (Graphics BBS) – used in the Melbourne area.
 GT-Power
 L.S.D. BBS – written by The Slavelord of The Humble Guys (THG).
 Infusion – written by Skaboy (Grant Olney) of ACiD Productions.
 The Major BBS
 MAUS
 Maximus
 McBBS – by Derek E. McDonald.
 MikroKOM
 H-Kom
 TPCS
 Opus-CBCS – first written by Wynn Wagner III.
 PCBoard
 PegaSys
 ProBoard BBS – written by Philippe Leybaert (Belgium).
 Pyroto Mountain
 QuickBBS – written by Adam Hudson, with assistance by Phil Becker.
 RBBS-PC
 RemoteAccess – written by Andrew Milner.
 Renegade – written by Cott Lang.
 RoboBOARD/FX – written by Seth Hamilton.
 Searchlight BBS (SLBBS)
 Spitfire
 SuperBBS – by Aki Antman and Risto Virkkala.
 TBBS
 TCL
 Telegard
 TriBBS
 TAG
 Virtual Advanced – also known as VBBS.
 Waffle – written by Tom Dell, and supported UUCP (and Fidonet through extensions).
 Wildcat! – originally by Mustang Software.
 Worldgroup – The latest version of MajorBBS, the last released by Galacticomm.

OS/2 
 AdeptXBBS
 Maximus
 PCBoard
 Virtual Advanced – also known as VBBS.
 Wildcat! – originally by Mustang Software.  It was not an OS/2 software package, but included code to run in a DOS box under OS/2.
 Xenia (BBS) mailer software

Tandy TRS-80 
 Forum 80
 TBBS - by Phil Becker, for the Model III/4

Unix and compatible 
 Citadel – including Citadel/UX, Dave's Own Citadel.
 Falken – Linux versions by Chris Whitacre, past MS-DOS versions written by Herb Rose.
 Firebird BBS – Linux-based.
 LysKOM
 Maple BBS
 MBSE BBS – formerly by Michiel Broek (till 2013). After that actively maintained (2019) on SourceForge.
 Maximus
 OpenTG – OpenTelegard BBS
 PCBoard v16 – formerly by CDC, now by MP Solutions, LLC.
 PicoSpan
 Sklaffkom  – Unix-based.
 Waffle (BBS software)

References 

BBS
Bulletin board system