This is a partial list of unnumbered minor planets for principal provisional designations assigned during 16–30 September 2003. Since this period yielded a high number of provisional discoveries, it is further split into several standalone pages. , a total of 551 bodies remain unnumbered for this period. Objects for this year are listed on the following pages: A–E · F–G · H–L · M–R · Si · Sii · Siii · Siv · T · Ui · Uii · Uiii · Uiv · V · Wi · Wii and X–Y. Also see previous and next year.
S
|- id="2003 SW273" bgcolor=#FA8072
| 0 || || MCA || 18.2 || data-sort-value="0.68" | 680 m || multiple || 2003–2020 || 14 Dec 2020 || 174 || align=left | Disc.: LINEAR || |- id="2003 SE274" bgcolor=#d6d6d6 | 0 || || MBA-O || 16.04 || 3.4 km || multiple || 2003–2021 || 18 Apr 2021 || 170 || align=left | Disc.: LONEOSAlt.: 2012 JB44 || |- id="2003 SH274" bgcolor=#d6d6d6 | 0 || || MBA-O || 17.3 || 1.9 km || multiple || 2003–2021 || 18 Jan 2021 || 106 || align=left | Disc.: LONEOSAlt.: 2014 UM42 || |- id="2003 SQ274" bgcolor=#d6d6d6 | 0 || || MBA-O || 16.5 || 2.8 km || multiple || 1997–2020 || 17 Oct 2020 || 105 || align=left | Disc.: Spacewatch || |- id="2003 SZ274" bgcolor=#E9E9E9 | 3 || || MBA-M || 18.9 || data-sort-value="0.92" | 920 m || multiple || 2003–2017 || 08 Dec 2017 || 23 || align=left | Disc.: Spacewatch || |- id="2003 SC276" bgcolor=#fefefe | 3 || || MBA-I || 18.8 || data-sort-value="0.52" | 520 m || multiple || 2003–2017 || 21 Nov 2017 || 33 || align=left | Disc.: SpacewatchAlt.: 2010 VJ42 || |- id="2003 SN276" bgcolor=#E9E9E9 | 2 || || MBA-M || 18.0 || 1.4 km || multiple || 2003–2021 || 06 Oct 2021 || 48 || align=left | Disc.: Spacewatch || |- id="2003 SS276" bgcolor=#E9E9E9 | 0 || || MBA-M || 17.5 || 1.3 km || multiple || 2003–2020 || 21 Jul 2020 || 54 || align=left | Disc.: SpacewatchAlt.: 2016 NG47 || |- id="2003 SE277" bgcolor=#E9E9E9 | 0 || || MBA-M || 17.07 || 2.1 km || multiple || 2003–2022 || 07 Jan 2022 || 269 || align=left | Disc.: LINEARAlt.: 2012 TQ211 || |- id="2003 SO277" bgcolor=#fefefe | 0 || || MBA-I || 17.8 || data-sort-value="0.82" | 820 m || multiple || 2000–2020 || 26 Dec 2020 || 164 || align=left | Disc.: LINEAR || |- id="2003 SC278" bgcolor=#fefefe | 2 || || MBA-I || 18.1 || data-sort-value="0.71" | 710 m || multiple || 2003–2020 || 22 Jun 2020 || 121 || align=left | Disc.: LINEAR || |- id="2003 SY278" bgcolor=#fefefe | 0 || || MBA-I || 18.9 || data-sort-value="0.49" | 490 m || multiple || 2003–2021 || 18 Jan 2021 || 35 || align=left | Disc.: SpacewatchAdded on 22 July 2020Alt.: 2013 TE78 || |- id="2003 SZ278" bgcolor=#E9E9E9 | 0 || || MBA-M || 18.24 || data-sort-value="0.95" | 950 m || multiple || 2003–2021 || 29 Nov 2021 || 62 || align=left | Disc.: LPL/Spacewatch IIAdded on 24 December 2021 || |- id="2003 SE279" bgcolor=#E9E9E9 | 1 || || MBA-M || 18.22 || 1.3 km || multiple || 2003–2021 || 08 Sep 2021 || 28 || align=left | Disc.: LPL/Spacewatch IIAdded on 19 October 2020 || |- id="2003 SF279" bgcolor=#d6d6d6 | 0 || || MBA-O || 16.91 || 2.3 km || multiple || 2003–2021 || 14 Aug 2021 || 95 || align=left | Disc.: LPL/Spacewatch IIAdded on 22 July 2020Alt.: 2010 LM83, 2015 FO69 || |- id="2003 SK280" bgcolor=#FA8072 | 2 || || MCA || 19.1 || data-sort-value="0.45" | 450 m || multiple || 2003–2019 || 17 Dec 2019 || 30 || align=left | Disc.: Spacewatch || |- id="2003 SM280" bgcolor=#E9E9E9 | 0 || || MBA-M || 17.7 || 1.2 km || multiple || 1999–2020 || 20 Oct 2020 || 140 || align=left | Disc.: NEAT || |- id="2003 SS280" bgcolor=#d6d6d6 | 0 || || MBA-O || 16.5 || 2.8 km || multiple || 2003–2021 || 08 Jan 2021 || 61 || align=left | Disc.: SpacewatchAlt.: 2014 TO53 || |- id="2003 SW280" bgcolor=#E9E9E9 | 0 || || MBA-M || 17.85 || 1.1 km || multiple || 2003–2021 || 06 Jan 2021 || 104 || align=left | Disc.: NEAT || |- id="2003 SV283" bgcolor=#d6d6d6 | 0 || || MBA-O || 17.5 || 1.8 km || multiple || 2003–2020 || 11 Dec 2020 || 77 || align=left | Disc.: LINEARAdded on 17 January 2021Alt.: 2014 NJ42 || |- id="2003 SW286" bgcolor=#E9E9E9 | 0 || || MBA-M || 17.9 || data-sort-value="0.78" | 780 m || multiple || 2003–2021 || 08 Jan 2021 || 92 || align=left | Disc.: NEATAlt.: 2013 BG40 || |- id="2003 SG287" bgcolor=#E9E9E9 | 1 || || MBA-M || 19.1 || data-sort-value="0.84" | 840 m || multiple || 2003–2017 || 08 Dec 2017 || 20 || align=left | Disc.: Spacewatch || |- id="2003 SJ287" bgcolor=#d6d6d6 | 0 || || MBA-O || 17.1 || 2.1 km || multiple || 2001–2019 || 15 Nov 2019 || 64 || align=left | Disc.: SpacewatchAlt.: 2014 SO292 || |- id="2003 SM287" bgcolor=#fefefe | 0 || || MBA-I || 18.2 || data-sort-value="0.68" | 680 m || multiple || 2003–2020 || 14 Dec 2020 || 99 || align=left | Disc.: SpacewatchAlt.: 2009 HZ68, 2010 VA156, 2012 FE4, 2015 AU260, 2016 RK13 || |- id="2003 SP287" bgcolor=#d6d6