Key takeaways
- Siemens' SIMATIC S7-300 web page says the S7-300 / ET 200M system families will be available until 2033. (Siemens' SIMATIC S7-300 page, https://www.siemens.com/en-us/products/simatic/s7-300/, read October 17, 2026)
- Siemens' S7-300/S7-400 to S7-1500 guide lists a recommended S7-1500 CPU against 37 S7-300 CPU order numbers (Table 7-1, pp. 82–83); 1 of them is on our shelves now.
- For the other S7-300 order numbers we stock (25 right now) this page names no successor and gives no status: not covered.
- No status is shown for any single order number: everything here is family-level, from the Siemens documents listed at the end, each with its page.
- The stock columns are live: what we have on the shelf now, at the price you pay.
What this page covers, and what it doesn't. Everything below comes from the 3 Siemens sources listed at the end, read on October 17, 2026, each statement with its page. These are statements about the S7-300 family as a whole: we show no lifecycle status for any single order number. Where a Siemens table lists an exact order number, we show what that table maps it to, with the table and page; that is Siemens' suggestion for a migration, for reference only, not a status and not a drop-in swap. Every other order number is marked “not covered”: we don't name a successor of our own.
Is the SIMATIC S7-300 still made?
- Siemens' SIMATIC S7-300 web page says the S7-300 / ET 200M system families will be available until 2033. (Siemens' SIMATIC S7-300 page, read October 17, 2026)
- Siemens' migration guide 109983811 (V1.2, January 2026) says the life cycle of the ET 200S and ET 200M I/O series is coming to an end, and that a common reason to modernize is replacing discontinued components whose spare-parts supply is no longer guaranteed in the long term. (Siemens migration guide 109983811, p. 4)
Siemens' migration path
- Siemens' guide lists a recommended S7-1500 CPU for the CPUs in its appendix tables and calls them a rough guide: reserves of the old CPU, memory, interfaces and plant layout decide the choice. (Siemens S7-300/S7-400 to S7-1500 migration guide 109478811, p. 18)
- Siemens marks its comparison tables as for reference only: a listed S7-1500 module is not automatically an equivalent, so check supply, signal voltage, channels and load against your plant. (Siemens S7-300/S7-400 to S7-1500 migration guide 109478811, p. 81)
- The existing ET 200 I/O can stay connected at first, but Siemens recommends moving all I/O to ET 200MP or ET 200SP (or other current ET 200) on PROFINET, if need be as a second step. (Siemens S7-300/S7-400 to S7-1500 migration guide 109478811, p. 21)
- For the program, the conversion tools are part of STEP 7 (TIA Portal), with a stand-alone migration tool and a readiness check. (Siemens S7-300/S7-400 to S7-1500 migration guide 109478811, p. 16)
S7-300 CPUs: Siemens' recommended S7-1500 CPU
Siemens' S7-300/S7-400 to S7-1500 migration guide (V1.1, May 2017) lists a recommended S7-1500 CPU against each of these S7-300 CPU order numbers, exactly as printed in its Table 7-1. Siemens calls the table a rough guide, for reference only (Siemens S7-300/S7-400 to S7-1500 migration guide 109478811, p. 18; Siemens S7-300/S7-400 to S7-1500 migration guide 109478811, p. 81).
Other S7-300 order numbers in our stock
Not covered. For these we show no status and name no successor: this page lists S7-1500 counterparts only for the CPUs in Siemens' Table 7-1. Siemens' guide also has comparison tables for S7-300 signal, communication and technology modules (pp. 88–89, 91 and 93–94), which it marks as for reference only; we have not put them on this page.
| Order number | Product (our listing) | Successor | In our stock |
|---|---|---|---|
6ES7 307-1BA00-0AA0 | Siemens 6ES7 307-1BA00-0AA0 SIMATIC S7-300 PS 307 Power Supply 24VDC 2A 230VAC | Not covered | 2 in stockfrom $22.89 |
6ES7 307-1BA01-0AA0 | Siemens Simatic 6ES7307-1BA01-0AA0 PS307 Power Supply 120/230VAC 24VDC 2A S7-300 | Not covered | 1 in stockfrom $15.89 |
6ES7 307-1EA00-0AA0 | Siemens 6ES7 307-1EA00-0AA0 | Not covered | 2 in stockfrom $20.00 |
6ES7 307-1KA01-0AA0 | Siemens 6ES7307-1KA01-0AA0 SIMATIC S7-300 PS307 Power Supply 120/230V 24VDC 10A | Not covered | 2 in stockfrom $15.89 |
6ES7 315-1AF03-0AB0 | Siemens 6ES7315-1AF03-0AB0 Simatic S7-300 CPU 315 PLC 24 VDC 0.7 A 48KB 0-60 C | Not covered | 3 in stockfrom $97.89 |
6ES7 315-2AH14-0AB0 | Siemens 6ES7315-2AH14-0AB0 Simatic S7-300 CPU 315-2 DP 24VDC 256KB MPI Profibus | Not covered | 1 in stockfrom $134.89 |
6ES7 321-1BH02-0AA0 | Siemens 6ES7321-1BH02-0AA0 SIMATIC S7-300 SM321 Digital Input Module 16DI 24VDC | Not covered | 2 in stockfrom $21.89 |
6ES7 321-1BH50-0AA0 | Siemens Simatic S7-300 6ES7321-1BH50-0AA0 Digital Input Module 16x DC 24V PLC | Not covered | 1 in stockfrom $13.89 |
6ES7 321-7RD00-0AB0 | Siemens 6ES7 321-7RD00-0AB0 SM321 Digital Input Module S7-300 PLC Automation | Not covered | 2 in stockfrom $151.89 |
6ES7 322-1BH01-0AA0 | Siemens Simatic S7-300 6ES7322-1BH01-0AA0 SM322 16DO Output Module Parts Repair | Not covered | 5 in stockfrom $6.89 |
6ES7 322-1BL00-0AA0 | Siemens Simatic S7-300 6ES7322-1BL00-0AA0 SM322 Digital Output Module 32DO 24VDC | Not covered | 45 in stockfrom $9.89 |
6ES7 322-1FF01-0AA0 | Siemens 6ES7 322-1FF01-0AA0 SIMATIC S7-300 SM 322 Digital Output Module 32-Point | Not covered | 2 in stockfrom $21.89 |
6ES7-322-1FH00 | Siemens Sinamatic 6ES7-322-1FH00 | Not covered | 1 in stockfrom $26.00 |
6ES7 322-1HF01-0AA0 | Siemens 6ES7322-1HF01-0AA0 Simatic S7-300 SM322 8 Relay Digital Output Module | Not covered | 20 in stockfrom $11.89 |
6ES7 322-1HF10-0AA0 | New Siemens 6ES7 322-1HF10-0AA0 Simatic 6ES7322-1HF10-0AA0 USA Shipping | Not covered | 1 in stockfrom $184.99 |
6ES7 322-1HF20-0AA0 | Siemens 6ES7322-1HF20-0AA0 SIMATIC S7-300 SM322 Relay Output Module 8DO 230V 5A | Not covered | 1 in stockfrom $26.89 |
6ES7 322-5HF00-0AB0 | Siemens 6ES7322-5HF00-0AB0 SIMATIC S7-300, Digital output SM 322, isolated, 8 DO | Not covered | 1 in stockfrom $349.99 |
6ES7 323-1BL00-0AA0 | Siemens 6ES7323-1BL00-0AA0 SIMATIC S7-300 SM 323 Digital I/O Module 16DI 16DO | Not covered | 1 in stockfrom $66.89 |
6ES7 341-1AH02-0AE0 | Siemens 6ES7 341-1AH02-0AE0 RS232 Module Comm Processor | Not covered | 2 in stockfrom $499.90 |
6ES7 350-2AH00-0AE0 | Siemens 6ES7350-2AH00-0AE0 SIMATIC S7-300 FM350-2 Counter Module 8-Channel PLC | Not covered | 2 in stockfrom $115.89 |
6ES7 365-0BA01-0AA0 | Siemens 6ES7 365-0BA01-0AA0 | Not covered | 5 in stockfrom $15.00 |
6ES7 370-0AA01-0AA0 | Siemens 6ES7370-0AA01-0AA0 Simatic S7-300 DM 370 Dummy Module Placeholder Slot | Not covered | 11 in stockfrom $10.89 |
6ES7 378-2AB00-0AC0 | Siemens Simatic 6ES7 378-2AB00-0AC0 6GK1140-1AA00 962-3AA00-0AC0 EXM 378-2 | Not covered | 1 in stockfrom $709.00 |
6ES7 380-7BA00-0AA0 | Siemens 6ES7 380-7BA00-0AA0 Jumper Bar 6ES73807BA000AA0 | Not covered | 14 in stockfrom $13.00 |
6ES7 388-4BN00-0AC0 | Siemens 6ES7388-4BN00-0AC0 SIMATIC M7-300 CPU388-4 w/ 6ES7952-1KP00-0AA0 | Not covered | 1 in stockfrom $1,299.00 |
Sources (read October 17, 2026; page numbers are the ones printed on each page):
- Guide for Migrating SIMATIC S7-300/S7-400 to SIMATIC S7-1500 and TIA Portal – Siemens, V1.1, May 2017 (PDF, 97 pages)
- Migration Guide for Tunnel Automation from SIMATIC S7-400H with PROFIBUS to S7-1500H with PROFINET – Siemens, V1.2, January 2026 (PDF, 28 pages)
- SIMATIC S7-300 (Siemens product page) – read October 17, 2026
Siemens updates its documents: check the current edition, and the details of your plant, before you order or plan a migration.
Keep it running or migrate?
Many plants do both: spares for the S7-300 systems that must keep running, and a dated plan to move off the platform at planned shutdowns. Every unit we stock is photographed; check the order number and product version on the label before you buy.
Safety first: switch off and lock out the rack's supply and any separately powered I/O before you change a SIMATIC module, following Siemens' instructions and your site's lockout/tagout procedure. Field wiring can be live from other sources even when the PLC is off – verify before you touch it.
Frequently asked questions
Is the SIMATIC S7-300 still made?
Siemens' SIMATIC S7-300 web page says the S7-300 / ET 200M system families will be available until 2033. (Siemens' SIMATIC S7-300 page, https://www.siemens.com/en-us/products/simatic/s7-300/, read October 17, 2026) We show no status for individual order numbers.
What replaces an S7-300 CPU?
Siemens' guide 109478811 lists a recommended S7-1500 CPU for the S7-300 CPUs in its Table 7-1 – not every S7-300 CPU is in it – for example 6ES7 513-1AL01-0AB0 (CPU 1513-1PN) against the 6ES7 315-2AG10-0AB0 (CPU 315-2DP) (Table 7-1, Siemens S7-300/S7-400 to S7-1500 migration guide 109478811, p. 82). Siemens' guide lists a recommended S7-1500 CPU for the CPUs in its appendix tables and calls them a rough guide: reserves of the old CPU, memory, interfaces and plant layout decide the choice. (Siemens S7-300/S7-400 to S7-1500 migration guide 109478811, p. 18)
What replaces S7-300 I/O and other modules?
This page names successors only for the CPUs in Siemens' Table 7-1: other modules are not covered. The existing ET 200 I/O can stay connected at first, but Siemens recommends moving all I/O to ET 200MP or ET 200SP (or other current ET 200) on PROFINET, if need be as a second step. (Siemens S7-300/S7-400 to S7-1500 migration guide 109478811, p. 21) The same guide has comparison tables for S7-300 signal, communication and technology modules (pp. 88–89, 91 and 93–94), which it marks as for reference only (Siemens S7-300/S7-400 to S7-1500 migration guide 109478811, p. 81).
Can I still buy SIMATIC S7-300 parts?
We stock surplus and used units – the tables show what is on our shelves now – and source the ones we don't have: send the order numbers through the quote form. Purchase orders are welcome; payment is due before we ship.